Consul cluster fails to start after a restart due to /etc/consul.d/server_metadata.json: invalid config key last_seen_unix

[elgatopanzon]

Overview of the Issue

After deploying a 3 node consul cluster successfully, Consul writes out to the file /etc/consul.d/server_metadata.json and then complains about the key index last_seen_unix after restarting/reloading Consul. The servers in the cluster fail to start up until this file is removed.

Contents of the file:

{"last_seen_unix":1719273473}

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Reproduction Steps

Steps to reproduce this issue:

1. Create a cluster with 3 server nodes, 0 clients
2. Stop Consul
3. Start Consul
4. They will not start, each one logging the same error

Operating system and Environment details

Debian 12, Consul 1.18.2 (not running 1.19.0 due to DNS bug with Nomad)

Log Fragments

Jun 24 18:31:43 mynode systemd[1]: Started consul.service - "HashiCorp Consul - A service mesh solution".
Jun 24 18:31:43 mynode consul[3835]: ==> failed to parse /etc/consul.d/server_metadata.json: 1 error occurred:
Jun 24 18:31:43 mynode consul[3835]:         * invalid config key last_seen_unix
Jun 24 18:31:43 mynode systemd[1]: consul.service: Main process exited, code=exited, status=1/FAILURE
Jun 24 18:31:43 mynode systemd[1]: consul.service: Failed with result 'exit-code'.