Add a timeout for archive_wal

[madtibo]

The archive_wal script can get stuck, for example, following a network problem:

/usr/bin/sss_ssh_knownhostsproxy -p 22 <ip>
ssh -n -- <ip> readlink -m -- /backups/pitr/
/bin/bash /usr/bin/archive_wal pg_wal/000000010000038C00000032

There is no automatic way to finalise the process.
It would be nice to configure a timeout that will error out when triggered.

[madtibo]

Either add a /usr/bin/timeout before de command in the PostgreSQL archive_command parameter.

Or do it inside the script:

• http://mywiki.wooledge.org/BashFAQ/068
• https://wincent.com/wiki/Executing_a_command_with_a_timeout_in_Bash