Locked unused files, can't delete about moosefs

[xandrus]

Hi,
Thank you for this information.
I would like to add that in MooseFS we have implemented security mechanism to prevent unknow chunks against immediately deletion.

For example if you some how connect chunkserver from different MooseFS instance, MooseFS master will mark all chunks from such chunkserver as locked and after one week files will be deleted. So you have some time to react.

We had few cases connected with such a scenario.
So to prevent unknown chunks deletion we add such a mechanism.

Do you still have this 693 chunks in locked state?
Do you have any dropped mfsmount sessions?
Maybe your chunkserver was disconnected some time?

Can you send us some system logs from MooseFS master?

[zcalusic]

Hello, and tnx for the answer.

The chunks eventually got deleted, I'd say it took even more than a week, but I'm not sure. This is one and only installation all the time, although I did some operations like relocating master to another host, and copying chunks from one server to another. Both of them succeeded without problems. I can't rememeber the exact timing. In any case, all seems perfect now.

In the master logs there are some (on two occasions) anomalies of the type:

chunkserver (1.2.3.4) has nonexistent chunk (000000000001AFAD_00000001), so create it for future deletion

And some of the type:

(2.3.4.5:9422 -> 6.7.8.9:9422) chunk: 000000000003C906 replication status: Wrong chunk version

I typically don't have dropped sessions, even if I catch one, most likely I'll terminate it manually.

I forgot to mention one thing, I'm breaking one rule from the recommended setup, the chunkservers don't have exclusive access to the disks, instead they are using free space on otherwise already used partitions. I understand this can produce higher rate of replications due to usage leveling, although I can live with that. I don't know if this higher rate of replication can provoke other problems.

[zcalusic]

Since this hasn't happen since, and resolved all by itself, I will close the issue. Probably the info could be added in the documentation and/or FAQ.