Setting up Pacemaker (pcs) with DRBD

Latest response

I am working on a high-availability NFS passive-active cluster with two nodes. I am on RHEL 7.6. Both nodes have DRBD setup on them with two partitions, /prod (/dev/drbd0) and /base (/dev/drbd1).

The drbd configuration is as follows:

resource r0 {
  volume 0 {
    device    /dev/drbd0;
    disk      /dev/VG03/prod;
    meta-disk internal;
  }
  volume 1 {
    device    /dev/drbd1;
    disk      /dev/VG03/base;
    meta-disk internal;
  }
  on node1 {
    address   x.x.x.112:7789;
  }
  on node2 {
    address   x.x.x.111:7789;
  }
}

Now, that's all fine and dandy, but I'm stuck at setting up drbd WITH the cluster.

I setup the cluster, then ran these commands:

pcs -f drbd_cfg resource create NFS ocf:linbit:drbd drbd_resource=r0 op monitor interval=60s

pcs -f drbd_cfg resource master r0Clone NFS master-max=1 master-node-max=1 clone-max=2 clone-node-max=1 notify=true

pcs -f drbd_cfg resource show

pcs cluster cib-push drbd_cfg --config

Those commands are setting up the resource with the cluster, but I haven't yet figured out setting up the file systems.

Current output of pcs status:

ken@node1:~$ sudo pcs status
Cluster name: nfs

WARNINGS:
No stonith devices and stonith-enabled is not false

Stack: corosync
Current DC: node2 (version 1.1.19-8.el7_6.5-c3c624ea3d) - partition with quorum
Last updated: Fri Jun  7 19:48:18 2019
Last change: Fri Jun  7 17:32:04 2019 by root via cibadmin on node1

2 nodes configured
2 resources configured

Online: [ node1 node2 ]

Full list of resources:

 Master/Slave Set: r0Clone [NFS]
     Masters: [ node1 ]
     Slaves: [ node2 ]

Daemon Status:
  corosync: active/enabled
  pacemaker: active/enabled
  pcsd: active/enabled

Theoretically, would these be the next commands I need to run?

pcs cluster cib fs_cfg

pcs -f fs_cfg resource create prod Filesystem device="/dev/drbd0" directory="/prod" fstype="xfs"

pcs -f fs_cfg resource create base Filesystem device="/dev/drbd1" directory="/base" fstype="xfs"

pcs -f fs_cfg constraint colocation add prod with r0Clone INFINITY with-rsc-role=Master

pcs -f fs_cfg constraint colocation add base with r0Clone INFINITY with-rsc-role=Master

pcs -f fs_cfg constraint order promote r0Clone then start prod

pcs -f fs_cfg constraint order promote r0Clone then start base

Since I'm working with two volumes, it makes this a little more difficult. Has anybody worked with this before?

Responses

Unfortunately, I can't help you with DRBD. I tried setting it up and never got it to work quite how I was wanting. Instead I went with GlusterFS and nfs-ganesha for high-availability NFS cluster. Just wanted to throw that out there and see if it might be a viable solution for you! -Alex

Thanks! DRBD would be much easier to setup if I wasn't needing it for two partitions. The configuration gets very confusing, since there's only one example out there on linbit's website. Appreciate the info!