[gpfsug-discuss] Filesystem descriptor discs for GNR

[Luke Sudbery]

We have a 2 site Lenovo DSS-G based filesystem, which with (some of the data) replicated across the 2 sites. We'd like to a 3rd filesystem descriptor disk so we can lose one site and still have filesystem descriptor quorum. But this seems incompatible unless we make new vdisks - which we can't do on non native raid servers.

We've added a new NSD which now has a free disc, but can't add that disk as descOnly.

Adding the new descriptor disk to the system pool says:
  mmadddisk: A storage pool may not contain both vdisk NSDs and non-vdisk NSDs.

Adding the new disk to a new system_desc pool says:
  mmadddisk: Disk usage descOnly is incompatible with storage pool system_desc.

Tried adding config to specify the system_desc pool is for metadataOnly and it still says it's incompatible.

There is no mention of descOnly disks here: https://www.ibm.com/support/knowledgecenter/en/SSFKCN_4.1.0/com.ibm.cluster.gpfs.v4r1.gpfs200.doc/bl1adv_planning.htm

Is it possible add a non-vdisk descOnly NSD to a dss-g/GNR solution?

Cheers,

Luke

-- 
Luke Sudbery
Architecture, Infrastructure and Systems
Advanced Research Computing, IT Services
Room 103, Computer Centre G5, Elms Road

Please note I don't work on Monday and work from home on Friday.