DRBD parse error, a syncer option keyword expected

Question

Built a drbd v9.2 kernel module on Linux 5.14.0-162.6.1 The module is loaded but I get an error.

resource data {

  protocol  C;
  device    /dev/drbd0;
  disk      /dev/sdb1;
  meta-disk internal;

  net {
    cram-hmac-alg sha1;
    shared-secret "m0293995m0293996";
    #allow-two-primaries;
    ko-count 4;
    max-buffers 8000;
    max-epoch-size 8000;
    sndbuf-size 0;
  }

  syncer {
    verify-alg md5;
    rate 50M;
  }

  startup {
    wfc-timeout 10;
  }
  on m0293995 {
    address 192.168.0.1:7788;
  }
  on m0293996 {
    address 192.168.0.2:7788;
  }
}

Whats causing this error ?

$ drbdadm create-md data
/etc/drbd.d/data.res:20: Parse error: 'a syncer option keyword' expected,
    but got 'rate'

Answer 1

Please check the appropriate man page. For DRBD 9.x it would be drbd.conf-9.0 for 8.x it would simply be drbd.conf.

The use of the syncer stanza was deprecated but is still valid for backward-compatibility. This now should be within the disk stanza of the configuration.

rate is not a valid option though, you want to use resync-rate.

Please also note that with the dynamic sync-rate controller the resync-rate is simply used a starting value. See the c-plan-ahead, c-fill-target, c-max-rate, and c-min-rate, options for tuning the dynamic sync-rate controller. If you wish to disable the dynamic sync-rate, set the c-plan-ahead to zero.

For more information on tuning the sync-rate controller see this knowledgebase article here: https://kb.linbit.com/tuning-drbds-resync-controller