[SOLVED] ceph mds question

[RobFantini]

so we have 7 nodes set up to use ceph.

I am starting to test ceph-fs

does it make sense to have all nodes be a mds?

or like mons limit it to 3 ?

for 'hotstandby parameter option' - I assume all mds systems should use that option - if not please advise.

thanks

 

[wolfgang]

Hi,

or like mons limit it to 3 ?

mds work active-backup so only one MDS is active and the other wait for takeover.

 

[RobFantini]

Hi,

mds work active-backup so only one MDS is active and the other wait for takeover.

OK and
Is it a good practice in a 5 or 7 node cluster to have all nodes be a MDS backup?

 

[Alwin]

Is it a good practice in a 5 or 7 node cluster to have all nodes be a MDS backup?

Not really, the standby MDS need to sync with the primary MDS and as long as you don't see the MDS getting overloaded with client traffic, there is no need to put away the extra resources.

 

[RobFantini]

Not really, the standby MDS need to sync with the primary MDS and as long as you don't see the MDS getting overloaded with client traffic, there is no need to put away the extra resources.

OK then I'll just use 3.