summaryrefslogtreecommitdiff
path: root/doc/administration/reference_architectures/2k_users.md
blob: 3b9a8f966c8531977a2ca0c4c54e723ca5c86e76 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
---
stage: Systems
group: Distribution
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
---

# Reference architecture: up to 2,000 users **(FREE SELF)**

This page describes GitLab reference architecture for up to 2,000 users.
For a full list of reference architectures, see
[Available reference architectures](index.md#available-reference-architectures).

> - **Supported users (approximate):** 2,000
> - **High Availability:** No. For a highly-available environment, you can
>   follow a modified [3K reference architecture](3k_users.md#supported-modifications-for-lower-user-counts-ha).
> - **Estimated Costs:** [See cost table](index.md#cost-to-run)
> - **Cloud Native Hybrid:** [Yes](#cloud-native-hybrid-reference-architecture-with-helm-charts-alternative)
> - **Validation and test results:** The Quality Engineering team does [regular smoke and performance tests](index.md#validation-and-test-results) to ensure the reference architectures remain compliant
>   - **Test requests per second (RPS) rates:** API: 40 RPS, Web: 4 RPS, Git (Pull): 4 RPS, Git (Push): 1 RPS
>   - **[Latest Results](https://gitlab.com/gitlab-org/quality/performance/-/wikis/Benchmarks/Latest/2k)**

| Service                                  | Nodes          | Configuration           | GCP             | AWS            | Azure          |
|------------------------------------------|----------------|-------------------------|-----------------|----------------|----------------|
| Load balancer<sup>3</sup>                | 1              | 2 vCPU, 1.8 GB memory   | `n1-highcpu-2`  | `c5.large`     | `F2s v2`       |
| PostgreSQL<sup>1</sup>                   | 1              | 2 vCPU, 7.5 GB memory   | `n1-standard-2` | `m5.large`     | `D2s v3`       |
| Redis<sup>2</sup>                        | 1              | 1 vCPU, 3.75 GB memory  | `n1-standard-1` | `m5.large`     | `D2s v3`       |
| Gitaly                                   | 1              | 4 vCPU, 15 GB memory    | `n1-standard-4` | `m5.xlarge`    | `D4s v3`       |
| GitLab Rails                             | 2              | 8 vCPU, 7.2 GB memory   | `n1-highcpu-8`  | `c5.2xlarge`   | `F8s v2`       |
| Monitoring node                          | 1              | 2 vCPU, 1.8 GB memory   | `n1-highcpu-2`  | `c5.large`     | `F2s v2`       |
| Object storage<sup>4</sup>               | Not applicable | Not applicable          | Not applicable  | Not applicable | Not applicable |
| NFS server (non-Gitaly)                  | 1              | 4 vCPU, 3.6 GB memory   | `n1-highcpu-4`  | `c5.xlarge`    | `F4s v2`       |

<!-- markdownlint-disable MD029 -->
1. Can be optionally run on reputable third-party external PaaS PostgreSQL solutions. [Google Cloud SQL](https://cloud.google.com/sql/docs/postgres/high-availability#normal) and [Amazon RDS](https://aws.amazon.com/rds/) are known to work, however Azure Database for PostgreSQL is **not recommended** due to [performance issues](https://gitlab.com/gitlab-org/quality/reference-architectures/-/issues/61). Consul is primarily used for PostgreSQL high availability so can be ignored when using a PostgreSQL PaaS setup. However it is also used optionally by Prometheus for Omnibus auto host discovery.
2. Can be optionally run as reputable third-party external PaaS Redis solutions. Google Memorystore and AWS ElastiCache are known to work.
3. Can be optionally run as reputable third-party load balancing services (LB PaaS). AWS ELB is known to work.
4. Should be run on reputable third-party object storage (storage PaaS) for cloud implementations. Google Cloud Storage and AWS S3 are known to work.
<!-- markdownlint-enable MD029 -->

NOTE:
For all PaaS solutions that involve configuring instances, it is strongly recommended to implement a minimum of three nodes in three different availability zones to align with resilient cloud architecture practices.

```plantuml
@startuml 2k
skinparam linetype ortho

card "**External Load Balancer**" as elb #6a9be7

collections "**GitLab Rails** x3" as gitlab #32CD32
card "**Prometheus + Grafana**" as monitor #7FFFD4
card "**Gitaly**" as gitaly #FF8C00
card "**PostgreSQL**" as postgres #4EA7FF
card "**Redis**" as redis #FF6347
cloud "**Object Storage**" as object_storage #white

elb -[#6a9be7]-> gitlab
elb -[#6a9be7]--> monitor

gitlab -[#32CD32]--> gitaly
gitlab -[#32CD32]--> postgres
gitlab -[#32CD32]-> object_storage
gitlab -[#32CD32]--> redis

monitor .[#7FFFD4]u-> gitlab
monitor .[#7FFFD4]-> gitaly
monitor .[#7FFFD4]-> postgres
monitor .[#7FFFD4,norank]--> redis
monitor .[#7FFFD4,norank]u--> elb

@enduml
```

## Requirements

Before starting, you should take note of the following requirements / guidance for this reference architecture.

### Supported CPUs

This reference architecture was built and tested on Google Cloud Platform (GCP) using the
[Intel Xeon E5 v3 (Haswell)](https://cloud.google.com/compute/docs/cpu-platforms)
CPU platform. On different hardware you may find that adjustments, either lower
or higher, are required for your CPU or node counts. For more information, see
our [Sysbench](https://github.com/akopytov/sysbench)-based
[CPU benchmarks](https://gitlab.com/gitlab-org/quality/performance/-/wikis/Reference-Architectures/GCP-CPU-Benchmarks).

### Supported infrastructure

As a general guidance, GitLab should run on most infrastructure such as reputable Cloud Providers (AWS, GCP, Azure) and their services, or self managed (ESXi) that meet both the specs detailed above, as well as any requirements in this section. However, this does not constitute a guarantee for every potential permutation.

Be aware of the following specific call outs:

- [Azure Database for PostgreSQL](https://docs.microsoft.com/en-us/azure/postgresql/#:~:text=Azure%20Database%20for%20PostgreSQL%20is,high%20availability%2C%20and%20dynamic%20scalability.) is [not recommended](https://gitlab.com/gitlab-org/quality/reference-architectures/-/issues/61) due to known performance issues or missing features.
- [Azure Blob Storage](https://docs.microsoft.com/en-us/azure/storage/blobs/) is recommended to be configured with [Premium accounts](https://docs.microsoft.com/en-us/azure/storage/blobs/storage-blob-block-blob-premium) to ensure consistent performance.

## Setup components

To set up GitLab and its components to accommodate up to 2,000 users:

1. [Configure the external load balancing node](#configure-the-external-load-balancer)
   to handle the load balancing of the GitLab application services nodes.
1. [Configure PostgreSQL](#configure-postgresql), the database for GitLab.
1. [Configure Redis](#configure-redis).
1. [Configure Gitaly](#configure-gitaly), which provides access to the Git
   repositories.
1. [Configure the main GitLab Rails application](#configure-gitlab-rails)
   to run Puma, Workhorse, GitLab Shell, and to serve all frontend
   requests (which include UI, API, and Git over HTTP/SSH).
1. [Configure Prometheus](#configure-prometheus) to monitor your GitLab
   environment.
1. [Configure the object storage](#configure-the-object-storage) used for
   shared data objects.
1. [Configure Advanced Search](#configure-advanced-search) (optional) for faster,
   more advanced code search across your entire GitLab instance.
1. [Configure NFS](#configure-nfs-optional) (optional, and not recommended)
   to have shared disk storage service as an alternative to Gitaly or object
   storage.

## Configure the external load balancer

In a multi-node GitLab configuration, you'll need a load balancer to route
traffic to the application servers. The specifics on which load balancer to use
or its exact configuration is beyond the scope of GitLab documentation. We assume
that if you're managing multi-node systems like GitLab, you already have a load
balancer of choice and that the routing methods used are distributing calls evenly
between all nodes. Some load balancer examples include HAProxy (open-source),
F5 Big-IP LTM, and Citrix Net Scaler. This documentation outline the ports and
protocols needed for use with GitLab.

This architecture has been tested and validated with [HAProxy](https://www.haproxy.org/)
as the load balancer. Although other load balancers with similar feature sets
could also be used, those load balancers have not been validated.

The next question is how you will handle SSL in your environment. There are
several different options:

- [The application node terminates SSL](#application-node-terminates-ssl).
- [The load balancer terminates SSL without backend SSL](#load-balancer-terminates-ssl-without-backend-ssl)
  and communication is not secure between the load balancer and the application node.
- [The load balancer terminates SSL with backend SSL](#load-balancer-terminates-ssl-with-backend-ssl)
  and communication is *secure* between the load balancer and the application node.

### Application node terminates SSL

Configure your load balancer to pass connections on port 443 as `TCP` instead
of `HTTP(S)`. This will pass the connection unaltered to the application node's
NGINX service, which has the SSL certificate and listens to port 443.

For details about managing SSL certificates and configuring NGINX, see the
[NGINX HTTPS documentation](https://docs.gitlab.com/omnibus/settings/nginx.html#enable-https).

### Load balancer terminates SSL without backend SSL

Configure your load balancer to use the `HTTP(S)` protocol instead of `TCP`.
The load balancer will be responsible for both managing SSL certificates and
terminating SSL.

Due to communication between the load balancer and GitLab not being secure,
you'll need to complete some additional configuration. For details, see the
[NGINX proxied SSL documentation](https://docs.gitlab.com/omnibus/settings/nginx.html#supporting-proxied-ssl).

### Load balancer terminates SSL with backend SSL

Configure your load balancers (or single balancer, if you have only one) to use
the `HTTP(S)` protocol rather than `TCP`. The load balancers will be
responsible for the managing SSL certificates for end users.

Traffic will be secure between the load balancers and NGINX in this scenario,
and there's no need to add a configuration for proxied SSL. However, you'll
need to add a configuration to GitLab to configure SSL certificates. For
details about managing SSL certificates and configuring NGINX, see the
[NGINX HTTPS documentation](https://docs.gitlab.com/omnibus/settings/nginx.html#enable-https).

### Readiness checks

Ensure the external load balancer only routes to working services with built
in monitoring endpoints. The [readiness checks](../../user/admin_area/monitoring/health_check.md)
all require [additional configuration](../monitoring/ip_whitelist.md)
on the nodes being checked, otherwise, the external load balancer will not be able to
connect.

### Ports

The basic load balancer ports you should use are described in the following
table:

| Port    | Backend Port | Protocol                 |
| ------- | ------------ | ------------------------ |
| 80      | 80           | HTTP (*1*)               |
| 443     | 443          | TCP or HTTPS (*1*) (*2*) |
| 22      | 22           | TCP                      |

- (*1*): [Web terminal](../../ci/environments/index.md#web-terminals-deprecated) support
  requires your load balancer to correctly handle WebSocket connections.
  When using HTTP or HTTPS proxying, your load balancer must be configured
  to pass through the `Connection` and `Upgrade` hop-by-hop headers. For
  details, see the [web terminal](../integration/terminal.md) integration guide.
- (*2*): When using the HTTPS protocol for port 443, you'll need to add an SSL
  certificate to the load balancers. If you need to terminate SSL at the
  GitLab application server, use the TCP protocol.

If you're using GitLab Pages with custom domain support you will need some
additional port configurations. GitLab Pages requires a separate virtual IP
address. Configure DNS to point the `pages_external_url` from
`/etc/gitlab/gitlab.rb` to the new virtual IP address. For more information,
see the [GitLab Pages documentation](../pages/index.md).

| Port    | Backend Port  | Protocol  |
| ------- | ------------- | --------- |
| 80      | Varies (*1*)  | HTTP      |
| 443     | Varies (*1*)  | TCP (*2*) |

- (*1*): The backend port for GitLab Pages depends on the
  `gitlab_pages['external_http']` and `gitlab_pages['external_https']`
  settings. For details, see the [GitLab Pages documentation](../pages/index.md).
- (*2*): Port 443 for GitLab Pages must use the TCP protocol. Users can
  configure custom domains with custom SSL, which wouldn't be possible if SSL
  was terminated at the load balancer.

#### Alternate SSH Port

Some organizations have policies against opening SSH port 22. In this case,
it may be helpful to configure an alternate SSH hostname that instead allows
users to use SSH over port 443. An alternate SSH hostname requires a new
virtual IP address compared to the previously described GitLab HTTP
configuration.

Configure DNS for an alternate SSH hostname, such as `altssh.gitlab.example.com`:

| LB Port | Backend Port | Protocol |
| ------- | ------------ | -------- |
| 443     | 22           | TCP      |

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>

## Configure PostgreSQL

In this section, you'll be guided through configuring an external PostgreSQL database
to be used with GitLab.

### Provide your own PostgreSQL instance

If you're hosting GitLab on a cloud provider, you can optionally use a
managed service for PostgreSQL.

A reputable provider or solution should be used for this. [Google Cloud SQL](https://cloud.google.com/sql/docs/postgres/high-availability#normal) and [Amazon RDS](https://aws.amazon.com/rds/) are known to work, however Azure Database for PostgreSQL is **not recommended** due to [performance issues](https://gitlab.com/gitlab-org/quality/reference-architectures/-/issues/61).

If you use a cloud-managed service, or provide your own PostgreSQL:

1. Set up PostgreSQL according to the
   [database requirements document](../../install/requirements.md#database).
1. Create a `gitlab` username with a password of your choice. The `gitlab` user
   needs privileges to create the `gitlabhq_production` database.
1. Configure the GitLab application servers with the appropriate details.
   This step is covered in [Configuring the GitLab Rails application](#configure-gitlab-rails).

See [Configure GitLab using an external PostgreSQL service](../postgresql/external.md) for
further configuration steps.

### Standalone PostgreSQL using Omnibus GitLab

1. SSH in to the PostgreSQL server.
1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab
   package of your choice. Be sure to follow _only_ installation steps 1 and 2
   on the page.
1. Generate a password hash for PostgreSQL. This assumes you will use the default
   username of `gitlab` (recommended). The command will request a password
   and confirmation. Use the value that is output by this command in the next
   step as the value of `POSTGRESQL_PASSWORD_HASH`.

   ```shell
   sudo gitlab-ctl pg-password-md5 gitlab
   ```

1. Edit `/etc/gitlab/gitlab.rb` and add the contents below, updating placeholder
   values appropriately.

   - `POSTGRESQL_PASSWORD_HASH` - The value output from the previous step
   - `APPLICATION_SERVER_IP_BLOCKS` - A space delimited list of IP subnets or IP
     addresses of the GitLab application servers that will connect to the
     database. Example: `%w(123.123.123.123/32 123.123.123.234/32)`

   ```ruby
   # Disable all components except PostgreSQL related ones
   roles(['postgres_role'])

   # Set the network addresses that the exporters used for monitoring will listen on
   node_exporter['listen_address'] = '0.0.0.0:9100'
   postgres_exporter['listen_address'] = '0.0.0.0:9187'
   postgres_exporter['dbname'] = 'gitlabhq_production'
   postgres_exporter['password'] = 'POSTGRESQL_PASSWORD_HASH'

   # Set the PostgreSQL address and port
   postgresql['listen_address'] = '0.0.0.0'
   postgresql['port'] = 5432

   # Replace POSTGRESQL_PASSWORD_HASH with a generated md5 value
   postgresql['sql_user_password'] = 'POSTGRESQL_PASSWORD_HASH'

   # Replace APPLICATION_SERVER_IP_BLOCK with the CIDR address of the application node
   postgresql['trust_auth_cidr_addresses'] = %w(127.0.0.1/32 APPLICATION_SERVER_IP_BLOCK)

   # Prevent database migrations from running on upgrade automatically
   gitlab_rails['auto_migrate'] = false
   ```

1. Copy the `/etc/gitlab/gitlab-secrets.json` file from the first Omnibus node you configured and add or replace
   the file of the same name on this server. If this is the first Omnibus node you are configuring then you can skip this step.

1. [Reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect.
1. Note the PostgreSQL node's IP address or hostname, port, and
   plain text password. These will be necessary when configuring the
   [GitLab application server](#configure-gitlab-rails) later.

Advanced [configuration options](https://docs.gitlab.com/omnibus/settings/database.html)
are supported and can be added if needed.

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>

## Configure Redis

In this section, you'll be guided through configuring an external Redis instance
to be used with GitLab.

### Provide your own Redis instance

Redis version 5.0 or higher is required, as this is what ships with
Omnibus GitLab packages starting with GitLab 13.0. Older Redis versions
do not support an optional count argument to SPOP which is now required for
[Merge Trains](../../ci/pipelines/merge_trains.md).

In addition, GitLab makes use of certain commands like `UNLINK` and `USAGE` which
were introduced only in Redis 4.

Managed Redis from cloud providers such as AWS ElastiCache will work. If these
services support high availability, be sure it is not the Redis Cluster type.

Note the Redis node's IP address or hostname, port, and password (if required).
These will be necessary when configuring the
[GitLab application servers](#configure-gitlab-rails) later.

### Standalone Redis using Omnibus GitLab

The Omnibus GitLab package can be used to configure a standalone Redis server.
The steps below are the minimum necessary to configure a Redis server with
Omnibus:

1. SSH in to the Redis server.
1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab
   package of your choice. Be sure to follow _only_ installation steps 1 and 2
   on the page.
1. Edit `/etc/gitlab/gitlab.rb` and add the contents:

   ```ruby
   ## Enable Redis
   roles(["redis_master_role"])

   redis['bind'] = '0.0.0.0'
   redis['port'] = 6379
   redis['password'] = 'SECRET_PASSWORD_HERE'

   gitlab_rails['enable'] = false

   # Set the network addresses that the exporters used for monitoring will listen on
   node_exporter['listen_address'] = '0.0.0.0:9100'
   redis_exporter['listen_address'] = '0.0.0.0:9121'
   redis_exporter['flags'] = {
         'redis.addr' => 'redis://0.0.0.0:6379',
         'redis.password' => 'SECRET_PASSWORD_HERE',
   }
   ```

1. Copy the `/etc/gitlab/gitlab-secrets.json` file from the first Omnibus node you configured and add or replace
   the file of the same name on this server. If this is the first Omnibus node you are configuring then you can skip this step.

1. [Reconfigure Omnibus GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect.

1. Note the Redis node's IP address or hostname, port, and
   Redis password. These will be necessary when
   [configuring the GitLab application servers](#configure-gitlab-rails) later.

Advanced [configuration options](https://docs.gitlab.com/omnibus/settings/redis.html)
are supported and can be added if needed.

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>

## Configure Gitaly

[Gitaly](../gitaly/index.md) server node requirements are dependent on data size,
specifically the number of projects and those projects' sizes.

NOTE:
The Reference Architecture specs have been designed with good headroom in mind
but for Gitaly, increased specs or switching to Gitaly Cluster
may be required for notably large data sets or load.

Due to Gitaly having notable input and output requirements, we strongly
recommend that all Gitaly nodes use solid-state drives (SSDs). These SSDs
should have a throughput of at least 8,000
input/output operations per second (IOPS) for read operations and 2,000 IOPS
for write operations. These IOPS values are initial recommendations, and may be
adjusted to greater or lesser values depending on the scale of your
environment's workload. If you're running the environment on a Cloud provider,
refer to their documentation about how to configure IOPS correctly.

Be sure to note the following items:

- The GitLab Rails application shards repositories into
  [repository storage paths](../repository_storage_paths.md).
- A Gitaly server can host one or more storage paths.
- A GitLab server can use one or more Gitaly server nodes.
- Gitaly addresses must be specified to be correctly resolvable for *all*
  Gitaly clients.
- Gitaly servers must not be exposed to the public internet, as Gitaly's network
  traffic is unencrypted by default. The use of a firewall is highly recommended
  to restrict access to the Gitaly server. Another option is to
  [use TLS](#gitaly-tls-support).

NOTE:
The token referred to throughout the Gitaly documentation is an arbitrary
password selected by the administrator. This token is unrelated to tokens
created for the GitLab API or other similar web API tokens.

The following procedure describes how to configure a single Gitaly server named
`gitaly1.internal` with the secret token `gitalysecret`. We assume your GitLab
installation has two repository storages: `default` and `storage1`.

To configure the Gitaly server, on the server node you want to use for Gitaly:

1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab
   package of your choice. Be sure to follow _only_ installation steps 1 and 2
   on the page, and _do not_ provide the `EXTERNAL_URL` value.
1. Edit the Gitaly server node's `/etc/gitlab/gitlab.rb` file to configure
   storage paths, enable the network listener, and to configure the token:

<!--
Updates to example must be made at:
- https://gitlab.com/gitlab-org/charts/gitlab/blob/master/doc/advanced/external-gitaly/external-omnibus-gitaly.md#configure-omnibus-gitlab
- https://gitlab.com/gitlab-org/gitlab/blob/master/doc/administration/gitaly/index.md#gitaly-server-configuration
- all reference architecture pages
-->

   ```ruby
   # Avoid running unnecessary services on the Gitaly server
   postgresql['enable'] = false
   redis['enable'] = false
   nginx['enable'] = false
   puma['enable'] = false
   sidekiq['enable'] = false
   gitlab_workhorse['enable'] = false
   prometheus['enable'] = false
   alertmanager['enable'] = false
   grafana['enable'] = false
   gitlab_exporter['enable'] = false
   gitlab_kas['enable'] = false

   # Prevent database migrations from running on upgrade automatically
   gitlab_rails['auto_migrate'] = false

   # Configure the gitlab-shell API callback URL. Without this, `git push` will
   # fail. This can be your 'front door' GitLab URL or an internal load
   # balancer.
   gitlab_rails['internal_api_url'] = 'https://gitlab.example.com'

   # Gitaly
   gitaly['enable'] = true

   # Make Gitaly accept connections on all network interfaces. You must use
   # firewalls to restrict access to this address/port.
   # Comment out following line if you only want to support TLS connections
   gitaly['listen_addr'] = "0.0.0.0:8075"
   gitaly['prometheus_listen_addr'] = "0.0.0.0:9236"

   # Gitaly and GitLab use two shared secrets for authentication, one to authenticate gRPC requests
   # to Gitaly, and a second for authentication callbacks from GitLab-Shell to the GitLab internal API.
   # The following two values must be the same as their respective values
   # of the GitLab Rails application setup
   gitaly['auth_token'] = 'gitalysecret'
   gitlab_shell['secret_token'] = 'shellsecret'

   # Set the network addresses that the exporters used for monitoring will listen on
   node_exporter['listen_address'] = '0.0.0.0:9100'

   git_data_dirs({
     'default' => {
       'path' => '/var/opt/gitlab/git-data'
     },
     'storage1' => {
       'path' => '/mnt/gitlab/git-data'
     },
   })
   ```

1. Copy the `/etc/gitlab/gitlab-secrets.json` file from the first Omnibus node you configured and add or replace
   the file of the same name on this server. If this is the first Omnibus node you are configuring then you can skip this step.

1. [Reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect.

1. Confirm that Gitaly can perform callbacks to the internal API:

   ```shell
   sudo /opt/gitlab/embedded/bin/gitaly-hooks check /var/opt/gitlab/gitaly/config.toml
   ```

### Gitaly TLS support

Gitaly supports TLS encryption. To be able to communicate
with a Gitaly instance that listens for secure connections you will need to use `tls://` URL
scheme in the `gitaly_address` of the corresponding storage entry in the GitLab configuration.

You will need to bring your own certificates as this isn't provided automatically.
The certificate, or its certificate authority, must be installed on all Gitaly
nodes (including the Gitaly node using the certificate) and on all client nodes
that communicate with it following the procedure described in
[GitLab custom certificate configuration](https://docs.gitlab.com/omnibus/settings/ssl.html#install-custom-public-certificates).

NOTE:
The self-signed certificate must specify the address you use to access the
Gitaly server. If you are addressing the Gitaly server by a hostname, add it as a Subject Alternative
Name. If you are addressing the Gitaly server by its IP address, you must add it
as a Subject Alternative Name to the certificate.

It's possible to configure Gitaly servers with both an unencrypted listening
address (`listen_addr`) and an encrypted listening address (`tls_listen_addr`)
at the same time. This allows you to do a gradual transition from unencrypted to
encrypted traffic, if necessary.

To configure Gitaly with TLS:

1. Create the `/etc/gitlab/ssl` directory and copy your key and certificate there:

   ```shell
   sudo mkdir -p /etc/gitlab/ssl
   sudo chmod 755 /etc/gitlab/ssl
   sudo cp key.pem cert.pem /etc/gitlab/ssl/
   sudo chmod 644 key.pem cert.pem
   ```

1. Copy the cert to `/etc/gitlab/trusted-certs` so Gitaly will trust the cert when
   calling into itself:

   ```shell
   sudo cp /etc/gitlab/ssl/cert.pem /etc/gitlab/trusted-certs/
   ```

1. Edit `/etc/gitlab/gitlab.rb` and add:

   <!-- Updates to following example must also be made at https://gitlab.com/gitlab-org/charts/gitlab/blob/master/doc/advanced/external-gitaly/external-omnibus-gitaly.md#configure-omnibus-gitlab -->

   ```ruby
   gitaly['tls_listen_addr'] = "0.0.0.0:9999"
   gitaly['certificate_path'] = "/etc/gitlab/ssl/cert.pem"
   gitaly['key_path'] = "/etc/gitlab/ssl/key.pem"
   ```

1. Delete `gitaly['listen_addr']` to allow only encrypted connections.
1. Save the file and [reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure).

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>

## Configure GitLab Rails

This section describes how to configure the GitLab application (Rails) component.

In our architecture, we run each GitLab Rails node using the Puma webserver, and
have its number of workers set to 90% of available CPUs, with four threads. For
nodes running Rails with other components, the worker value should be reduced
accordingly. We've determined that a worker value of 50% achieves a good balance,
but this is dependent on workload.

On each node perform the following:

1. If you're [using NFS](#configure-nfs-optional):

   1. If necessary, install the NFS client utility packages using the following
      commands:

      ```shell
      # Ubuntu/Debian
      apt-get install nfs-common

      # CentOS/Red Hat
      yum install nfs-utils nfs-utils-lib
      ```

   1. Specify the necessary NFS mounts in `/etc/fstab`.
      The exact contents of `/etc/fstab` will depend on how you chose
      to configure your NFS server. See the [NFS documentation](../nfs.md)
      for examples and the various options.

   1. Create the shared directories. These may be different depending on your NFS
      mount locations.

      ```shell
      mkdir -p /var/opt/gitlab/.ssh /var/opt/gitlab/gitlab-rails/uploads /var/opt/gitlab/gitlab-rails/shared /var/opt/gitlab/gitlab-ci/builds /var/opt/gitlab/git-data
      ```

1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab
   package of your choice. Be sure to follow _only_ installation steps 1 and 2
   on the page.
1. Create or edit `/etc/gitlab/gitlab.rb` and use the following configuration.
   To maintain uniformity of links across nodes, the `external_url`
   on the application server should point to the external URL that users will use
   to access GitLab. This would be the URL of the [load balancer](#configure-the-external-load-balancer)
   which will route traffic to the GitLab application server:

   ```ruby
   external_url 'https://gitlab.example.com'

   # Gitaly and GitLab use two shared secrets for authentication, one to authenticate gRPC requests
   # to Gitaly, and a second for authentication callbacks from GitLab-Shell to the GitLab internal API.
   # The following two values must be the same as their respective values
   # of the Gitaly setup
   gitlab_rails['gitaly_token'] = 'gitalysecret'
   gitlab_shell['secret_token'] = 'shellsecret'

   git_data_dirs({
     'default' => { 'gitaly_address' => 'tcp://gitaly1.internal:8075' },
     'storage1' => { 'gitaly_address' => 'tcp://gitaly1.internal:8075' },
     'storage2' => { 'gitaly_address' => 'tcp://gitaly2.internal:8075' },
   })

   ## Disable components that will not be on the GitLab application server
   roles(['application_role'])
   gitaly['enable'] = false
   nginx['enable'] = true

   ## PostgreSQL connection details
   gitlab_rails['db_adapter'] = 'postgresql'
   gitlab_rails['db_encoding'] = 'unicode'
   gitlab_rails['db_host'] = '10.1.0.5' # IP/hostname of database server
   gitlab_rails['db_password'] = 'DB password'

   ## Redis connection details
   gitlab_rails['redis_port'] = '6379'
   gitlab_rails['redis_host'] = '10.1.0.6' # IP/hostname of Redis server
   gitlab_rails['redis_password'] = 'Redis Password'

   # Set the network addresses that the exporters used for monitoring will listen on
   node_exporter['listen_address'] = '0.0.0.0:9100'
   gitlab_workhorse['prometheus_listen_addr'] = '0.0.0.0:9229'
   sidekiq['listen_address'] = "0.0.0.0"
   # Set number of Sidekiq threads per queue process to the recommend number of 10
   sidekiq['max_concurrency'] = 10
   puma['listen'] = '0.0.0.0'

   # Add the monitoring node's IP address to the monitoring whitelist and allow it to
   # scrape the NGINX metrics. Replace placeholder `monitoring.gitlab.example.com` with
   # the address and/or subnets gathered from the monitoring node
   gitlab_rails['monitoring_whitelist'] = ['<MONITOR NODE IP>/32', '127.0.0.0/8']
   nginx['status']['options']['allow'] = ['<MONITOR NODE IP>/32', '127.0.0.0/8']

   # Object Storage
   # This is an example for configuring Object Storage on GCP
   # Replace this config with your chosen Object Storage provider as desired
   gitlab_rails['object_store']['enabled'] = true
   gitlab_rails['object_store']['connection'] = {
     'provider' => 'Google',
     'google_project' => '<gcp-project-name>',
     'google_json_key_location' => '<path-to-gcp-service-account-key>'
   }
   gitlab_rails['object_store']['objects']['artifacts']['bucket'] = "<gcp-artifacts-bucket-name>"
   gitlab_rails['object_store']['objects']['external_diffs']['bucket'] = "<gcp-external-diffs-bucket-name>"
   gitlab_rails['object_store']['objects']['lfs']['bucket'] = "<gcp-lfs-bucket-name>"
   gitlab_rails['object_store']['objects']['uploads']['bucket'] = "<gcp-uploads-bucket-name>"
   gitlab_rails['object_store']['objects']['packages']['bucket'] = "<gcp-packages-bucket-name>"
   gitlab_rails['object_store']['objects']['dependency_proxy']['bucket'] = "<gcp-dependency-proxy-bucket-name>"
   gitlab_rails['object_store']['objects']['terraform_state']['bucket'] = "<gcp-terraform-state-bucket-name>"

   gitlab_rails['backup_upload_connection'] = {
     'provider' => 'Google',
     'google_project' => '<gcp-project-name>',
     'google_json_key_location' => '<path-to-gcp-service-account-key>'
   }
   gitlab_rails['backup_upload_remote_directory'] = "<gcp-backups-state-bucket-name>"

   ## Uncomment and edit the following options if you have set up NFS
   ##
   ## Prevent GitLab from starting if NFS data mounts are not available
   ##
   #high_availability['mountpoint'] = '/var/opt/gitlab/git-data'
   ##
   ## Ensure UIDs and GIDs match between servers for permissions via NFS
   ##
   #user['uid'] = 9000
   #user['gid'] = 9000
   #web_server['uid'] = 9001
   #web_server['gid'] = 9001
   #registry['uid'] = 9002
   #registry['gid'] = 9002
   ```

1. If you're using [Gitaly with TLS support](#gitaly-tls-support), make sure the
   `git_data_dirs` entry is configured with `tls` instead of `tcp`:

   ```ruby
   git_data_dirs({
     'default' => { 'gitaly_address' => 'tls://gitaly1.internal:9999' },
     'storage1' => { 'gitaly_address' => 'tls://gitaly1.internal:9999' },
     'storage2' => { 'gitaly_address' => 'tls://gitaly2.internal:9999' },
   })
   ```

   1. Copy the cert into `/etc/gitlab/trusted-certs`:

      ```shell
      sudo cp cert.pem /etc/gitlab/trusted-certs/
      ```

1. Copy the `/etc/gitlab/gitlab-secrets.json` file from the first Omnibus node you configured and add or replace
   the file of the same name on this server. If this is the first Omnibus node you are configuring then you can skip this step.

1. To ensure database migrations are only run during reconfigure and not automatically on upgrade, run:

   ```shell
   sudo touch /etc/gitlab/skip-auto-reconfigure
   ```

   Only a single designated node should handle migrations as detailed in the
   [GitLab Rails post-configuration](#gitlab-rails-post-configuration) section.

1. [Reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect.

1. Run `sudo gitlab-rake gitlab:gitaly:check` to confirm the node can connect to Gitaly.
1. Tail the logs to see the requests:

   ```shell
   sudo gitlab-ctl tail gitaly
   ```

When you specify `https` in the `external_url`, as in the previous example,
GitLab expects that the SSL certificates are in `/etc/gitlab/ssl/`. If the
certificates aren't present, NGINX will fail to start. For more information, see
the [NGINX documentation](https://docs.gitlab.com/omnibus/settings/nginx.html#enable-https).

### GitLab Rails post-configuration

1. Designate one application node for running database migrations during
   installation and updates. Initialize the GitLab database and ensure all
   migrations ran:

   ```shell
   sudo gitlab-rake gitlab:db:configure
   ```

   If you encounter a `rake aborted!` error message stating that PgBouncer is
   failing to connect to PostgreSQL, it may be that your PgBouncer node's IP
   address is missing from PostgreSQL's `trust_auth_cidr_addresses` in `gitlab.rb`
   on your database nodes. Before proceeding, see
   [PgBouncer error `ERROR:  pgbouncer cannot connect to server`](troubleshooting.md#pgbouncer-error-error-pgbouncer-cannot-connect-to-server).

1. [Configure fast lookup of authorized SSH keys in the database](../operations/fast_ssh_key_lookup.md).

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>

## Configure Prometheus

The Omnibus GitLab package can be used to configure a standalone Monitoring node
running [Prometheus](../monitoring/prometheus/index.md) and
[Grafana](../monitoring/performance/grafana_configuration.md):

1. SSH in to the Monitoring node.
1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab
   package of your choice. Be sure to follow _only_ installation steps 1 and 2
   on the page.
1. Edit `/etc/gitlab/gitlab.rb` and add the contents:

   ```ruby
   roles(['monitoring_role'])

   external_url 'http://gitlab.example.com'

   # Prometheus
   prometheus['listen_address'] = '0.0.0.0:9090'
   prometheus['monitor_kubernetes'] = false

   # Grafana
   grafana['enable'] = true
   grafana['admin_password'] = '<grafana_password>'
   grafana['disable_login_form'] = false

   # Nginx - For Grafana access
   nginx['enable'] = true
   ```

1. Prometheus also needs some scrape configurations to pull all the data from the various
   nodes where we configured exporters. Assuming that your nodes' IPs are:

   ```plaintext
   1.1.1.1: postgres
   1.1.1.2: redis
   1.1.1.3: gitaly1
   1.1.1.4: rails1
   1.1.1.5: rails2
   ```

   Add the following to `/etc/gitlab/gitlab.rb`:

   ```ruby
   prometheus['scrape_configs'] = [
     {
        'job_name': 'postgres',
        'static_configs' => [
        'targets' => ['1.1.1.1:9187'],
        ],
     },
     {
        'job_name': 'redis',
        'static_configs' => [
        'targets' => ['1.1.1.2:9121'],
        ],
     },
     {
        'job_name': 'gitaly',
        'static_configs' => [
        'targets' => ['1.1.1.3:9236'],
        ],
     },
     {
        'job_name': 'gitlab-nginx',
        'static_configs' => [
        'targets' => ['1.1.1.4:8060', '1.1.1.5:8060'],
        ],
     },
     {
        'job_name': 'gitlab-workhorse',
        'static_configs' => [
        'targets' => ['1.1.1.4:9229', '1.1.1.5:9229'],
        ],
     },
     {
        'job_name': 'gitlab-rails',
        'metrics_path': '/-/metrics',
        'static_configs' => [
        'targets' => ['1.1.1.4:8080', '1.1.1.5:8080'],
        ],
     },
     {
        'job_name': 'gitlab-sidekiq',
        'static_configs' => [
        'targets' => ['1.1.1.4:8082', '1.1.1.5:8082'],
        ],
     },
     {
        'job_name': 'node',
        'static_configs' => [
        'targets' => ['1.1.1.1:9100', '1.1.1.2:9100', '1.1.1.3:9100', '1.1.1.4:9100', '1.1.1.5:9100'],
        ],
     },
   ]
   ```

1. Save the file and [reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure).
1. In the GitLab UI, set `admin/application_settings/metrics_and_profiling` > Metrics - Grafana to `/-/grafana` to
`http[s]://<MONITOR NODE>/-/grafana`

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>

## Configure the object storage

GitLab supports using an object storage service for holding several types of
data, and is recommended over [NFS](#configure-nfs-optional). In general,
object storage services are better for larger environments, as object storage
is typically much more performant, reliable, and scalable.

GitLab has been tested on a number of object storage providers:

- [Amazon S3](https://aws.amazon.com/s3/)
- [Google Cloud Storage](https://cloud.google.com/storage)
- [Digital Ocean Spaces](https://www.digitalocean.com/products/spaces)
- [Oracle Cloud Infrastructure](https://docs.cloud.oracle.com/en-us/iaas/Content/Object/Tasks/s3compatibleapi.htm)
- [OpenStack Swift (S3 compatibility mode)](https://docs.openstack.org/swift/latest/s3_compat.html)
- [Azure Blob storage](https://docs.microsoft.com/en-us/azure/storage/blobs/storage-blobs-introduction)
- On-premises hardware and appliances from various storage vendors.
- MinIO. We have [a guide to deploying this](https://docs.gitlab.com/charts/advanced/external-object-storage/minio.html) within our Helm Chart documentation.

There are two ways of specifying object storage configuration in GitLab:

- [Consolidated form](../object_storage.md#consolidated-object-storage-configuration): A single credential is
  shared by all supported object types.
- [Storage-specific form](../object_storage.md#storage-specific-configuration): Every object defines its
  own object storage [connection and configuration](../object_storage.md#connection-settings).

Starting with GitLab 13.2, consolidated object storage configuration is available. It simplifies your GitLab configuration since the connection details are shared across object types. Refer to [Consolidated object storage configuration](../object_storage.md#consolidated-object-storage-configuration) guide for instructions on how to set it up.

GitLab Runner returns job logs in chunks which Omnibus GitLab caches temporarily on disk in `/var/opt/gitlab/gitlab-ci/builds` by default, even when using consolidated object storage. With default configuration, this directory needs to be shared via NFS on any GitLab Rails and Sidekiq nodes.

In GitLab 13.6 and later, it's also recommended to switch to [Incremental logging](../job_logs.md#incremental-logging-architecture), which uses Redis instead of disk space for temporary caching of job logs. This is required when no NFS node has been deployed.

For configuring object storage in GitLab 13.1 and earlier, or for storage types not
supported by consolidated configuration form, refer to the following guides based
on what features you intend to use:

|Object storage type|Supported by consolidated configuration?|
|-------------------|----------------------------------------|
| [Backups](../../raketasks/backup_restore.md#uploading-backups-to-a-remote-cloud-storage) | No |
| [Job artifacts](../job_artifacts.md#using-object-storage) including archived job logs | Yes |
| [LFS objects](../lfs/index.md#storing-lfs-objects-in-remote-object-storage) | Yes |
| [Uploads](../uploads.md#using-object-storage) | Yes |
| [Container Registry](../packages/container_registry.md#use-object-storage) (optional feature) | No |
| [Merge request diffs](../merge_request_diffs.md#using-object-storage) | Yes |
| [Mattermost](https://docs.mattermost.com/administration/config-settings.html#file-storage)| No |
| [Packages](../packages/index.md#using-object-storage) (optional feature) | Yes |
| [Dependency Proxy](../packages/dependency_proxy.md#using-object-storage) (optional feature) | Yes |
| [Autoscale runner caching](https://docs.gitlab.com/runner/configuration/autoscale.html#distributed-runners-caching) (optional for improved performance) | No |
| [Terraform state files](../terraform_state.md#using-object-storage) | Yes |

Using separate buckets for each data type is the recommended approach for GitLab.
This ensures there are no collisions across the various types of data GitLab stores.
There are plans to [enable the use of a single bucket](https://gitlab.com/gitlab-org/gitlab/-/issues/292958)
in the future.

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>

## Configure Advanced Search **(PREMIUM SELF)**

You can leverage Elasticsearch and [enable Advanced Search](../../integration/advanced_search/elasticsearch.md)
for faster, more advanced code search across your entire GitLab instance.

Elasticsearch cluster design and requirements are dependent on your specific
data. For recommended best practices about how to set up your Elasticsearch
cluster alongside your instance, read how to
[choose the optimal cluster configuration](../../integration/advanced_search/elasticsearch.md#guidance-on-choosing-optimal-cluster-configuration).

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>

## Configure NFS (optional)

For improved performance, [object storage](#configure-the-object-storage),
along with [Gitaly](#configure-gitaly), are recommended over using NFS whenever
possible.

See how to [configure NFS](../nfs.md).

WARNING:
Engineering support for NFS for Git repositories is deprecated. Technical support is planned to be
unavailable from GitLab 15.0. No further enhancements are planned for this feature.

Read:

- [Gitaly and NFS Deprecation](../nfs.md#gitaly-and-nfs-deprecation).
- About the [correct mount options to use](../nfs.md#upgrade-to-gitaly-cluster-or-disable-caching-if-experiencing-data-loss).

## Cloud Native Hybrid reference architecture with Helm Charts (alternative)

As an alternative approach, you can also run select components of GitLab as Cloud Native
in Kubernetes via our official [Helm Charts](https://docs.gitlab.com/charts/).
In this setup, we support running the equivalent of GitLab Rails and Sidekiq nodes
in a Kubernetes cluster, named Webservice and Sidekiq respectively. In addition,
the following other supporting services are supported: NGINX, Task Runner, Migrations,
Prometheus, and Grafana.

Hybrid installations leverage the benefits of both cloud native and traditional
compute deployments. With this, _stateless_ components can benefit from cloud native
workload management benefits while _stateful_ components are deployed in compute VMs
with Omnibus to benefit from increased permanence.

The 2,000 reference architecture is not a highly-available setup. To achieve HA, you can follow a modified [3K reference architecture](3k_users.md#cloud-native-hybrid-reference-architecture-with-helm-charts-alternative).

NOTE:
This is an **advanced** setup. Running services in Kubernetes is well known
to be complex. **This setup is only recommended** if you have strong working
knowledge and experience in Kubernetes. The rest of this
section assumes this.

### Cluster topology

The following tables and diagram detail the hybrid environment using the same formats
as the normal environment above.

First are the components that run in Kubernetes. The recommendation at this time is to
use Google Cloud's Kubernetes Engine (GKE) or AWS Elastic Kubernetes Service (EKS) and associated machine types, but the memory
and CPU requirements should translate to most other providers. We hope to update this in the
future with further specific cloud provider details.

| Service                                       | Nodes | Configuration          | GCP             | AWS          | Min Allocatable CPUs and Memory |
|-----------------------------------------------|-------|------------------------|-----------------|--------------|---------------------------------|
| Webservice                                    | 3     | 8 vCPU, 7.2 GB memory  | `n1-highcpu-8`  | `c5.2xlarge` | 23.7 vCPU, 16.9 GB memory       |
| Sidekiq                                       | 2     | 2 vCPU, 7.5 GB memory  | `n1-standard-2` | `m5.large`   | 3.9 vCPU, 11.8 GB memory        |
| Supporting services such as NGINX, Prometheus | 2     | 1 vCPU, 3.75 GB memory | `n1-standard-1` | `m5.large`   | 1.9 vCPU, 5.5 GB memory         |

- For this setup, we **recommend** and regularly [test](index.md#validation-and-test-results)
[Google Kubernetes Engine (GKE)](https://cloud.google.com/kubernetes-engine) and [Amazon Elastic Kubernetes Service (EKS)](https://aws.amazon.com/eks/). Other Kubernetes services may also work, but your mileage may vary.
- Nodes configuration is shown as it is forced to ensure pod vCPU / memory ratios and avoid scaling during **performance testing**.
  - In production deployments, there is no need to assign pods to nodes. A minimum of three nodes in three different availability zones is strongly recommended to align with resilient cloud architecture practices.

Next are the backend components that run on static compute VMs via Omnibus (or External PaaS
services where applicable):

| Service                    | Nodes          | Configuration          | GCP             | AWS            |
|----------------------------|----------------|------------------------|-----------------|----------------|
| PostgreSQL<sup>1</sup>     | 1              | 2 vCPU, 7.5 GB memory  | `n1-standard-2` | `m5.large`     |
| Redis<sup>2</sup>          | 1              | 1 vCPU, 3.75 GB memory | `n1-standard-1` | `m5.large`     |
| Gitaly                     | 1              | 4 vCPU, 15 GB memory   | `n1-standard-4` | `m5.xlarge`    |
| Object storage<sup>3</sup> | Not applicable | Not applicable         | Not applicable  | Not applicable |

<!-- Disable ordered list rule https://github.com/DavidAnson/markdownlint/blob/main/doc/Rules.md#md029---ordered-list-item-prefix -->
<!-- markdownlint-disable MD029 -->
1. Can be optionally run on reputable third-party external PaaS PostgreSQL solutions. [Google Cloud SQL](https://cloud.google.com/sql/docs/postgres/high-availability#normal) and [Amazon RDS](https://aws.amazon.com/rds/) are known to work, however Azure Database for PostgreSQL is **not recommended** due to [performance issues](https://gitlab.com/gitlab-org/quality/reference-architectures/-/issues/61). Consul is primarily used for PostgreSQL high availability so can be ignored when using a PostgreSQL PaaS setup. However it is also used optionally by Prometheus for Omnibus auto host discovery.
2. Can be optionally run on reputable third-party external PaaS Redis solutions. Google Memorystore and AWS ElastiCache are known to work.
3. Should be run on reputable third-party object storage (storage PaaS) for cloud implementations. Google Cloud Storage and AWS S3 are known to work.
<!-- markdownlint-enable MD029 -->

NOTE:
For all PaaS solutions that involve configuring instances, it is strongly recommended to implement a minimum of three nodes in three different availability zones to align with resilient cloud architecture practices.

```plantuml
@startuml 2k
skinparam linetype ortho

card "Kubernetes via Helm Charts" as kubernetes {
  card "**External Load Balancer**" as elb #6a9be7

  together {
    collections "**Webservice** x3" as gitlab #32CD32
    collections "**Sidekiq** x2" as sidekiq #ff8dd1
    card "**Supporting Services**" as support
  }
}

card "**Gitaly**" as gitaly #FF8C00
card "**PostgreSQL**" as postgres #4EA7FF
card "**Redis**" as redis #FF6347
cloud "**Object Storage**" as object_storage #white

elb -[#6a9be7]-> gitlab

gitlab -[#32CD32]--> gitaly
gitlab -[#32CD32]--> postgres
gitlab -[#32CD32]-> object_storage
gitlab -[#32CD32]--> redis

sidekiq -[#ff8dd1]--> gitaly
sidekiq -[#ff8dd1]-> object_storage
sidekiq -[#ff8dd1]--> postgres
sidekiq -[#ff8dd1]--> redis

@enduml
```

### Resource usage settings

The following formulas help when calculating how many pods may be deployed within resource constraints.
The [2k reference architecture example values file](https://gitlab.com/gitlab-org/charts/gitlab/-/blob/master/examples/ref/2k.yaml)
documents how to apply the calculated configuration to the Helm Chart.

#### Webservice

Webservice pods typically need about 1 vCPU and 1.25 GB of memory _per worker_.
Each Webservice pod consumes roughly 2 vCPUs and 2.5 GB of memory using
the [recommended topology](#cluster-topology) because two worker processes
are created by default and each pod has other small processes running.

For 2,000 users we recommend a total Puma worker count of around 12.
With the [provided recommendations](#cluster-topology) this allows the deployment of up to 6
Webservice pods with 2 workers per pod and 2 pods per node. Expand available resources using
the ratio of 1 vCPU to 1.25 GB of memory _per each worker process_ for each additional
Webservice pod.

For further information on resource usage, see the [Webservice resources](https://docs.gitlab.com/charts/charts/gitlab/webservice/#resources).

#### Sidekiq

Sidekiq pods should generally have 1 vCPU and 2 GB of memory.

[The provided starting point](#cluster-topology) allows the deployment of up to
2 Sidekiq pods. Expand available resources using the 1 vCPU to 2GB memory
ratio for each additional pod.

For further information on resource usage, see the [Sidekiq resources](https://docs.gitlab.com/charts/charts/gitlab/sidekiq/#resources).

<div align="right">
  <a type="button" class="btn btn-default" href="#setup-components">
    Back to setup components <i class="fa fa-angle-double-up" aria-hidden="true"></i>
  </a>
</div>