Today I was running clush -w @all 'sudo puppet agent --test' from the host tools-clushmaster-01.eqiad.wmflabs and some issues happened in the output.
In case of tools-docker-builder-05.tools.eqiad.wmflabs, this was:
tools-checker-01.tools.eqiad.wmflabs: Info: Loading facts in /var/lib/puppet/lib/facter/pe_version.rb
tools-docker-builder-05.tools.eqiad.wmflabs: ssh: connect to host tools-docker-builder-05.tools.eqiad.wmflabs port 22: Connection timed out
clush: tools-docker-builder-05.tools.eqiad.wmflabs: exited with exit code 255
tools-exec-1403.tools.eqiad.wmflabs: Info: Caching catalog for tools-exec-1403.tools.eqiad.wmflabs
@chasemp suggested that this is probably just a dead node.