Remove gearman from docs

Change-Id: Id10e41b23b2b01bcd4ec1b0f69645d1200acf415

1 files changed, 13 insertions, 22 deletions

diff --git a/doc/source/components.rst b/doc/source/components.rst
index 6d2ce043b..246442783 100644
--- a/doc/source/components.rst
+++ b/doc/source/components.rst
@@ -16,7 +16,6 @@ which is described below.
       Database [fontcolor=grey]
       Executor [href="#executor"]
       Finger [href="#finger-gateway"]
-      Gearman [shape=ellipse]
       Gerrit [fontcolor=grey]
       Merger [href="#merger"]
       Statsd [shape=ellipse fontcolor=grey]
@@ -26,18 +25,14 @@ which is described below.
       GitHub [fontcolor=grey]
       Web [href="#web-server"]
 
-      Merger -- Gearman
       Executor -- Statsd
       Executor -- "Job Node"
       Web -- Database
-      Web -- Gearman
       Web -- GitHub
       Web -- Zookeeper
       Web -- Executor
-      Finger -- Gearman
       Finger -- Executor
 
-      Gearman -- Scheduler;
       Scheduler -- Database;
       Scheduler -- Gerrit;
       Scheduler -- Zookeeper;
@@ -55,34 +50,30 @@ which is described below.
    :backlinks: none
 
 Each of the Zuul processes may run on the same host, or different
-hosts.  Within Zuul, the components communicate with the scheduler via
-the Gearman protocol, so each Zuul component needs to be able to
-connect to the host running the Gearman server (the scheduler has a
-built-in Gearman server which is recommended) on the Gearman port --
-TCP port 4730 by default.
+hosts.
 
-The Zuul scheduler communicates with Nodepool via the ZooKeeper
-protocol.  Nodepool requires an external ZooKeeper cluster, and the
-Zuul scheduler needs to be able to connect to the hosts in that
-cluster on TCP port 2181 or 2281.
+Zuul requires an external ZooKeeper cluster running at least ZooKeeper
+version 3.5.1, and all Zuul and Nodepool components need to be able to
+connect to the hosts in that cluster on a TLS-encrypted TCP port,
+typically 2281.
 
 Both the Nodepool launchers and Zuul executors need to be able to
-communicate with the hosts which nodepool provides.  If these are on
-private networks, the Executors will need to be able to route traffic
+communicate with the hosts which Nodepool provides.  If these are on
+private networks, the executors will need to be able to route traffic
 to them.
 
 Only Zuul fingergw and Zuul web need to be publicly accessible;
-executors never do. Executors should be accessible on TCP port 7900
-by fingergw and web.
+executors never do. Executors should be accessible on TCP port 7900 by
+fingergw and web.
 
 A database is required and configured in ``database`` section of
 ``/etc/zuul/zuul.conf``. Both Zuul scheduler and Zuul web will need
 access to it.
 
-If statsd is enabled, the executors and scheduler needs to be able to
-emit data to statsd.  Statsd can be configured to run on each host
-and forward data, or services may emit to a centralized statsd
-collector.  Statsd listens on UDP port 8125 by default.
+If statsd is enabled, the executors and schedulers need to be able to
+emit data to statsd.  Statsd can be configured to run on each host and
+forward data, or services may emit to a centralized statsd collector.
+Statsd listens on UDP port 8125 by default.
 
 A minimal Zuul system may consist of a :ref:`scheduler` and
 :ref:`executor` both running on the same host.  Larger installations