From f70fcf659eb4a304f592767ae403f646ad5bec0d Mon Sep 17 00:00:00 2001 From: Tim Gross Date: Thu, 6 Oct 2022 11:32:35 -0400 Subject: [PATCH] docs: 1.4.0 upgrade warning for keyring initialization (#14825) --- .../content/docs/upgrade/upgrade-specific.mdx | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/website/content/docs/upgrade/upgrade-specific.mdx b/website/content/docs/upgrade/upgrade-specific.mdx index 5215318e0..c9f310fc1 100644 --- a/website/content/docs/upgrade/upgrade-specific.mdx +++ b/website/content/docs/upgrade/upgrade-specific.mdx @@ -15,6 +15,21 @@ used to document those details separately from the standard upgrade flow. ## Nomad 1.4.0 +#### Possible Panic During Upgrades + +Nomad 1.4.0 initializes a keyring on the leader if one has not been previously +created, which writes a new raft entry. Users have reported that the keyring +initialization can cause a panic on older servers during upgrades. Following the +documented [upgrade process][] closely will reduce the risk of this panic. But +if a server with version 1.4.0 or higher becomes leader while servers with +versions before 1.4.0 are still in the cluster, the older servers will panic. + +The most likely scenario for this is if the leader is still on a version before +1.4.0 and is netsplit from the rest of the cluster or the server is restarted +without upgrading, and one of the 1.4.0 servers becomes the leader. + +You can recover from the panic by immediately upgrading the old servers. + #### Raft Protocol Version 2 Unsupported Raft protocol version 2 was deprecated in Nomad v1.3.0, and is being removed @@ -1514,3 +1529,4 @@ deleted and then Nomad 0.3.0 can be launched. [alloc_overlap]: https://github.com/hashicorp/nomad/issues/10440 [gh_10446]: https://github.com/hashicorp/nomad/pull/10446#issuecomment-1224833906 [gh_issue]: https://github.com/hashicorp/nomad/issues/new/choose +[upgrade process]: /docs/upgrade#upgrade-process