From b8ef47f6d6f214385695d5b1045fc7978746df8f Mon Sep 17 00:00:00 2001 From: freddygv Date: Tue, 18 Oct 2022 10:08:43 -0600 Subject: [PATCH] Add docs about upgrading primary mesh gateways Care must be taken when replacing mesh gateways in the primary datacenter, because if the old addresses become unreachable before the secondary datacenters receive the new addresses then the primary datacenter overall will become unreachable. This commit adds docs related to this class of upgrades. --- .../wan-federation-via-mesh-gateways.mdx | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/website/content/docs/connect/gateways/mesh-gateway/wan-federation-via-mesh-gateways.mdx b/website/content/docs/connect/gateways/mesh-gateway/wan-federation-via-mesh-gateways.mdx index 55a8194f54..3a995da947 100644 --- a/website/content/docs/connect/gateways/mesh-gateway/wan-federation-via-mesh-gateways.mdx +++ b/website/content/docs/connect/gateways/mesh-gateway/wan-federation-via-mesh-gateways.mdx @@ -184,3 +184,17 @@ expected result: - Ensure any API request that activates datacenter request forwarding. such as [`/v1/catalog/services?dc=`](/api-docs/catalog#dc-1) succeeds. + +### Upgrading the primary gateways + +Once federation has been established, updates for the addresses of new primary +gateways are propagated through the gateways in the primary themselves. If the primary +gateways are upgraded, and their previous instances are decommissioned before +the updates are propagated, then the primary datacenter will become unreachable. + +To safely upgrade primary gateways it is preferable to do one of the following: +- Avoid decommissioning primary gateway IP addresses, since the [primary_gateways](/docs/agent/config/config-files#primary_gateways) addresses configured on the secondary +servers acts as a fallback mechanism to re-establish connectivity to the primary. + +- Verify that addresses of the new mesh gateways in the primary were propagated +to the secondary datacenters before decommissioning the old mesh gateways in the primary.