diff options
| -rw-r--r-- | ovn/TODO | 4 | ||||
| -rw-r--r-- | ovn/controller/ovn-controller.8.xml | 6 | ||||
| -rw-r--r-- | ovn/ovn-architecture.7.xml | 54 | ||||
| -rw-r--r-- | ovn/ovn-sb.ovsschema | 4 | ||||
| -rw-r--r-- | ovn/ovn-sb.xml | 5 | ||||
| -rwxr-xr-x | tutorial/ovs-sandbox | 2 |
6 files changed, 65 insertions, 10 deletions
@@ -91,10 +91,6 @@ ** ovn-controller parameters and configuration. -*** Tunnel encapsulation to publish. - - Default: VXLAN? Geneve? - *** SSL configuration. Can probably get this from Open_vSwitch database. diff --git a/ovn/controller/ovn-controller.8.xml b/ovn/controller/ovn-controller.8.xml index 5d4c595a2..e1cb6a228 100644 --- a/ovn/controller/ovn-controller.8.xml +++ b/ovn/controller/ovn-controller.8.xml @@ -97,8 +97,10 @@ <p> <code>external_ids:ovn-encap-type</code> specifies the encapsulation type that a chassis should use to connect to - this node. Examples include <code>geneve</code>, - <code>vxlan</code>, and <code>stt</code>. + this node. Supported tunnel types for connecting + hypervisors are <code>geneve</code> and <code>stt</code>. + Gateways may use <code>geneve</code>, <code>vxlan</code>, + or <code>stt</code>. </p> </li> <li> diff --git a/ovn/ovn-architecture.7.xml b/ovn/ovn-architecture.7.xml index f1dfa5fdf..f0921410b 100644 --- a/ovn/ovn-architecture.7.xml +++ b/ovn/ovn-architecture.7.xml @@ -575,4 +575,58 @@ to reflect the update. </li> </ol> + + <h1>Design Decisions</h1> + + <h2>Supported Tunnel Encapsulations</h2> + <p> + For connecting hypervisors to each other, the only supported tunnel + encapsulations are Geneve and STT. Hypervisors may use VXLAN to + connect to gateways. We have limited support to these encapsulations + for the following reasons: + </p> + + <ul> + <li> + <p> + They support large amounts of metadata. In addition to + specifying the logical switch, we will likely want to indicate + the logical source port and where we are in the logical + pipeline. Geneve supports a 24-bit VNI field and TLV-based + extensions. The header of STT includes a 64-bit context id. + </p> + </li> + + <li> + <p> + They use randomized UDP or TCP source ports that allows + efficient distribution among multiple paths in environments that + use ECMP in their underlay. + </p> + </li> + + <li> + <p> + NICs are available that accelerate encapsulation and decapsulation. + </p> + </li> + </ul> + + <p> + Due to its flexibility, the preferred encapsulation between + hypervisors is Geneve. Some environments may want to use STT for + performance reasons until the NICs they use support hardware offload + of Geneve. + </p> + + <p> + For connecting to gateways, the only supported tunnel encapsulations + are VXLAN, Geneve, and STT. While support for Geneve is becoming + available for TOR (top-of-rack) switches, VXLAN is far more common. + Currently, gateways have a feature set that matches the capabilities + as defined by the VTEP schema, so fewer bits of metadata are + necessary. In the future, gateways that do not support + encapsulations with large amounts of metadata may continue to have a + reduced feature set. + </p> </manpage> diff --git a/ovn/ovn-sb.ovsschema b/ovn/ovn-sb.ovsschema index 9fd5363b2..363e664a0 100644 --- a/ovn/ovn-sb.ovsschema +++ b/ovn/ovn-sb.ovsschema @@ -17,7 +17,9 @@ "indexes": [["name"]]}, "Encap": { "columns": { - "type": {"type": "string"}, + "type": {"type": {"key": { + "type": "string", + "enum": ["set", ["geneve", "stt", "vxlan"]]}}}, "options": {"type": {"key": "string", "value": "string", "min": 0, diff --git a/ovn/ovn-sb.xml b/ovn/ovn-sb.xml index 29a1c885f..2afc9a190 100644 --- a/ovn/ovn-sb.xml +++ b/ovn/ovn-sb.xml @@ -166,8 +166,9 @@ <column name="type"> The encapsulation to use to transmit packets to this chassis. - Examples include <code>geneve</code>, <code>vxlan</code>, and - <code>stt</code>. + Hypervisors must use either <code>geneve</code> or + <code>stt</code>. Gateways may use <code>vxlan</code>, + <code>geneve</code>, or <code>stt</code>. </column> <column name="options"> diff --git a/tutorial/ovs-sandbox b/tutorial/ovs-sandbox index 8aa2ddd49..1520cb734 100755 --- a/tutorial/ovs-sandbox +++ b/tutorial/ovs-sandbox @@ -289,7 +289,7 @@ rungdb $gdb_vswitchd ovs-vswitchd --detach --no-chdir --pidfile -vconsole:off -- if $ovn; then ovs-vsctl set open . external-ids:system-id=56b18105-5706-46ef-80c4-ff20979ab068 ovs-vsctl set open . external-ids:ovn-remote=unix:"$sandbox"/db.sock - ovs-vsctl set open . external-ids:ovn-encap-type=vxlan + ovs-vsctl set open . external-ids:ovn-encap-type=geneve ovs-vsctl set open . external-ids:ovn-encap-ip=127.0.0.1 ovs-vsctl add-br br-int |