Hello, I was asking same question in #aurora channel and I still haven't found an answer so I am bringing this in mailing list with a proposal.
Is there a way to check the state of mesos-log (whether the its writable in VOTING state) through some HTTP check outside of aurora process on a non-leading aurora instance? We are trying to create external check that would determine whether the mesos-log is ready in case of aurora rolling update. When adding new instance to existing aurora cluster and we want to make sure that mesos-log is replicated and replica is ready to serve reads and writes. Currently we’re grep-ing java process log and looking for “Persisted replica status to VOTING”. I was pointed to /vars endpoint but I haven't found obvious answer there. I'd like to propose creating new HTTP endpoint "/loghealth" that would similarly to "/leaderhealth" return 200 when mesos-log is ready and 503 in case when mesos log throws exception. As for implementation I was thinking about doing simple read from log or write noop to log directly. Thanks!
