[DRBD-user] How to simulate a corruption for testing drbdadm verify ?

[Hervé Gautier]

Hi folks !

I am wondering how to create a corruption on a device used by a DRBD 
resource to test drbdadm verify ?

I am using DRBD 8.3.0
Here is my configuration

# cat etc/drbd.conf
global {
   usage-count no;
}
common {
   net {
      after-sb-0pri discard-older-primary;
      after-sb-1pri discard-secondary;
      after-sb-2pri disconnect;
   }
   syncer {
      rate 26M;
   }
}

resource drbd_xterm {
   protocol C;

   syncer {
      verify-alg crc32c;
   }

   disk {
      on-io-error detach;
   }

   on mcla {
      device    /dev/drbd20;
      disk      /dev/cciss/c0d2p1;
      address   192.168.1.10:7790;
      meta-disk internal;
   }
   on mclb {
      device    /dev/drbd20;
      disk      /dev/cciss/c0d2p1;
      address   192.168.1.11:7790;
      meta-disk internal;
   }
}


In Primary/Secondary configuration, is it possible and enough to run on 
the Secondary node, a
# dd if=/dev/zero of=/dev/cciss/c0d2p1 bs=512 count=1
On then a:
# drbdadm verify drbd_xterm

Thank in advance for any information and advice

Rv

-- 
Hervé GAUTIER