6七、DRDB基礎實戰

一、涉及機器

192.168.60.11 node1.ha.com

192.168.60.12 node2.ha.com

二、新增硬盤用於DRBD

ls /sys/class/scsi_host/

echo "- - -" > /sys/class/scsi_host/host0/scan

echo "- - -" > /sys/class/scsi_host/host1/scan

echo "- - -" > /sys/class/scsi_host/host2/scan

三、安裝配置DRBD

wget ftp://rpmfind.net/linux/atrpms/el6-x86_64/atrpms/stable/drbd-8.4.3-33.el6.x86_64.rpm

wget ftp://rpmfind.net/linux/atrpms/el6-x86_64/atrpms/stable/drbd-kmdl-2.6.32-431.el6-8.4.3-33.el6.x86_64.rpm

rpm -ivh drbd-8.4.3-33.el6.x86_64.rpm drbd-kmdl-2.6.32-431.el6-8.4.3-33.el6.x86_64.rpm

grep -v ^# /etc/drbd.d/global_common.conf | grep -v .*#

global {

        usage-count no;

}

common {

        handlers {

                pri-on-incon-degr "/usr/lib/drbd/notify-pri-on-incon-degr.sh; /usr/lib/drbd/notify-emergency-reboot.sh; echo b > /proc/sysrq-trigger ; reboot -f";

                pri-lost-after-sb "/usr/lib/drbd/notify-pri-lost-after-sb.sh; /usr/lib/drbd/notify-emergency-reboot.sh; echo b > /proc/sysrq-trigger ; reboot -f";

                local-io-error "/usr/lib/drbd/notify-io-error.sh; /usr/lib/drbd/notify-emergency-shutdown.sh; echo o > /proc/sysrq-trigger ; halt -f";

        }

        startup {

        }

        options {

        }

        disk {

                on-io-error detach;

        }

        net {

                protocol C;

                cram-hmac-alg "sha1";

                shared-secret "drbdsecret";

        }

        syncer {

                rate 1000M;

        }

}

cat /etc/drbd.d/web.res

resource web {

  on node1.ha.com {

    device    /dev/drbd0;

    disk      /dev/sdb;

    address   192.168.60.11:7789;

    meta-disk internal;

  }

  on node2.ha.com {

    device    /dev/drbd0;

    disk      /dev/sdb;

    address   192.168.60.12:7789;

    meta-disk internal;

  }

}

cd /etc/drbd.d/

scp global_common.conf web.res root@node2.ha.com:/etc/drbd.d

四、初始化資源並啓動服務、查看狀態（全部節點都要執行）

drbdadm create-md web                 

/etc/init.d/drbd start

drbd-overview（cat /proc/drbd）

drbdadm primary --force web

drbd-overview

 0:web/0  SyncSource Primary/Secondary UpToDate/Inconsistent C r---n- 

       [>....................] sync'ed:  4.6% (4888/5116)M

五、在主節點上建立文件系統並掛載

mke2fs -t ext4 /dev/drbd0

mount /dev/drbd0 /mnt

cd /mnt/

cp /etc/fstab /mnt/

六、主備切換

須要先將主的切換到備的，才能將原來備的切換到主的

主的切換到備的

umount /mnt

drbdadm secondary web 

drbd-overview

備的切換到主的

drbdadm primary web

drbd-overview 

mount /dev/drbd0 /mnt/

ls /mnt

umount /mnt

drbdadm secondary web

chkconfig drbd off

service drbd stop