How well does Seafile cope with missing memcached node?

Hi,
upon upgrading and rebooting nodes from our memcached cluster, I noticed that seahub apparently stops working whenerver one of the memcached nodes is unavailable. Which leaves me puzzled as I would expect a memcached-cluster setup to prevent exactly this? Anyone experiencing the same thing? Is this maybe a misconfiguration on our side?
Thanks in advance!

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Memcached Cluster support was dropped some time ago because they couldn’t fix certain problems and simply declared that it is not needed. … Which is not true, they simply did not seem to have this tested in a proper manner otherwise they would know that a memcached node failover (since clusters are not supported) causes serious issues in a Seafile cluster, especially with many connections/users.

A suitable solution would be to support redis, which is easy to cluster, a more modern approach and widely used for exactly this purpose in modern applications. It also scales a lot better than memcached.

@daniel.pan
Can you please elaborate on the future plans for this? A proper caching solution is required.

The same goes for CE as to replace memcached entirely or at least give the option to use redis.

Not providing a cluster solution for a cached backend makes the whole Seafile cluster not a real HA cluster.
When the memcached node breaks off the cluster crashes and users are loosing connections, Seahub is unresponsive and requires a service restart to start working properly again. This causes service interruptions and user support requests for they see error messages.

Thanks in advance for providing a proper caching cluster backend integration!

Redis support will be added in version 9.0.

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This is really good news. Especially enterprise customers will be very happy about it

We use yrmcds for this. Worked without problems for years and manages the failover automatically.

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