Serious Redis Object Cache Bug

  • Resolved Vanderlindemedia

    (@jvanderlinde)


    3 days, 6 hours ago

    Hi,

    An update struck one of my servers for some reason killing the Redis instance, or at least, it’s a nasty bug where some redis instances simply do no longer work that are within CageFS it seems. We’re actively trying to resolve this with Cloudlinux. It seems a update from RHEL caused issues with the above.

    But – this caused approx 15+ websites to crash – due to non existing Redis service not being available, and the websites that where running litespeed Caching and using object cache still proceeded to work (just without redis). It means that for whatever reason Redis is not available, the site simply won’t start using this plugin.

    I would suggest a fail-safe fallback, because i had to plunge into hundreds of sites to learn i had approx 15 running with above plugin that failed to start.

Viewing 4 replies - 1 through 4 (of 4 total)
  • Plugin Author Till Krüss

    (@tillkruess)

    3 days, 5 hours ago

    The object cache in WordPress must be online at all times, just like SQL. Otherwise the cache data will go stale and will cause data loss.

    Thread Starter Vanderlindemedia

    (@jvanderlinde)

    3 days, 5 hours ago

    Yes,

    In a fortunate update, that either happened through Directadmin or REL through Cloudlinux, Redis instance got nuked from multiple to a single one, making every website that used to run Redis crash that where using the Redis Object Cache plugin. Sites with Litespeed only did not crash – thus making it still operate but without the use of Redis.

    I would suggest there is a fallback once the Redis is no longer available (for whatever reason).

    Plugin Author Till Krüss

    (@tillkruess)

    3 days, 4 hours ago

    No, Litespeed is vulnerable to data corrupting.

    I suggest you set up supervisord and monitoring service to keep an eye on your infrastructure if it’s that critical.

    Thread Starter Vanderlindemedia

    (@jvanderlinde)

    3 days, 4 hours ago

    Well, at least it works,

    And it won’t crash the complete website after Redis seems to fail.

    So i assume your not taking this bug request then.

Viewing 4 replies - 1 through 4 (of 4 total)
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