Tugriceri Web Notes

 dd if=/dev/zero of=disk1.raw bs=1073741824 count=20
 1009  losetup -f disk1.raw
 1010  losetup -a
 1012  stat /dev/loop0
fdisk /dev/loop0
# rpm -Uvh http://elrepo.org/elrepo-release-6-4.el6.elrepo.noarch.rpm

# vi /etc/yum.repos.d/elrepo.repo

enabled=0

# yum –enablerepo=elrepo install drbd83-utils kmod-drbd83

SRV1# cat /etc/drbd.conf
#
# please have a a look at the example configuration file in
# /usr/share/doc/drbd83/drbd.conf
#
global {
   minor-count 1;
   usage-count no; # Participate in DRBD’s online usage counter at http://usage.drbd.org
}

resource zenoss {
    protocol C;
    startup {
       wfc-timeout        30;
       degr-wfc-timeout   60;
    }
    disk {
       on-io-error detach;
       fencing resource-only; 
    }
    handlers {
       pri-on-incon-degr “echo o > /proc/sysrq-trigger ; halt -f”; # reboot the system after a connection fail
       pri-lost-after-sb “echo o > /proc/sysrq-trigger ; halt -f”;
       outdate-peer “/usr/lib/heartbeat/drbd-peer-outdater”; 
    }
    net {
       after-sb-0pri discard-least-changes; # Self healing if split brean
       after-sb-1pri call-pri-lost-after-sb;
       max-buffers 2048; # datablock buffers used before writing to disk.
       ko-count 4; # Peer is dead if this count is exceeded.
    }
    syncer {
       rate   12M;
       al-extents 257;
    }
    on SRV1 {
       device      /dev/drbd0;
       disk        /dev/loop0;
       address     192.168.1.1:7789;
       meta-disk   internal;
    }
    on SRV2 {
       device      /dev/drbd0;
       disk        /dev/loop0;
       address     192.168.1.2:7789;
       meta-disk   internal;
   }
}

SRV1# cat /proc/drbd
SRV1# drbdsetup /dev/drbd0 primary -o
SRV1# cat /proc/drbd
SRV1# mkfs -t ext3 /dev/drbd0
SRV1# mkdir /mnt/drbd
SRV1# mount /dev/drbd0 /mnt/drbd
SRV1# cp /var/log/maillog /mnt/drbd
SRV1# ls /mnt/drbd

SRV1# umount /mnt/drbd
SRV1# drbdadm secondary zenoss

SRV2# drbdadm primary zenoss
SRV2# mkdir /mnt/drbd
SRV2# mount /dev/drbd0 /mnt/drbd
SRV2# ls /mnt/drbd