Linux下配置多路径

来源：Prodent Woo 的个人空间  

Linux下配置多路径
 
 
 
1、安装多路径软件包：
 
device-mapper-1.02.67-2.el5
 
device-mapper-event-1.02.67.2.el5
 
device-mapper-multipath-0.4.7-48.el5
 
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[root@RKDB01 Server]# rpm -ivh device-mapper-1.02.67-2.el5.x86_64.rpm   
 
warning: device-mapper-1.02.67-2.el5.x86_64.rpm: Header V3 DSA signature: NOKEY, key ID 37017186  
 
Preparing...                ########################################### [100%]  
 
        package device-mapper-1.02.67-2.el5.x86_64 is already installed  
 
[root@RKDB01 Server]# rpm -ivh device-mapper-event-1.02.67-2.el5.x86_64.rpm   
 
warning: device-mapper-event-1.02.67-2.el5.x86_64.rpm: Header V3 DSA signature: NOKEY, key ID 37017186  
 
Preparing...                ########################################### [100%]  
 
        package device-mapper-event-1.02.67-2.el5.x86_64 is already installed  
 
[root@RKDB01 Server]# rpm -ivh device-mapper-multipath-0.4.7-48.el5.x86_64.rpm   
 
warning: device-mapper-multipath-0.4.7-48.el5.x86_64.rpm: Header V3 DSA signature: NOKEY, key ID 37017186  
 
Preparing...                ########################################### [100%]  
 
        package device-mapper-multipath-0.4.7-48.el5.x86_64 is already installed  
 
 
 
2、设置开机启动，并检查安装包是否正常：
 
chkconfig --level 345 multipathd on
 
lsmod |grep dm_multipath
 
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[root@RKDB01 Server]# chkconfig --level 345  multipathd on  
 
[root@RKDB01 Server]# lsmod |grep dm_multipath  
 
dm_multipath           58969  0   
 
scsi_dh                42561  1 dm_multipath  
 
dm_mod                102417  4 dm_mirror,dm_multipath,dm_raid45,dm_log  
 
[root@RKDB01 Server]#   
 
 
 
3、配置multipathd 使其正常工作，编辑/etc/multipath.conf，开放如下内容：
 
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defaults {  
 
        udev_dir                /dev  
 
        polling_interval        10  
 
        selector                "round-robin 0"  
 
        path_grouping_policy    multibus  
 
        getuid_callout          "/sbin/scsi_id -g -u -s /block/%n"  
 
        prio_callout            none  
 
        path_checker            readsector0  
 
        rr_min_io               100  
 
        max_fds                 8192  
 
        rr_weight               priorities  
 
        failback                immediate  
 
        no_path_retry           fail  
 
        user_friendly_names     yes  
 
}  
 
blacklist {  
 
       wwid 26353900f02796769  
 
        devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"  
 
        devnode "^hd[a-z]"  
 
}  
 
 
 
4、并关闭如下内容
 
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#blacklist {  
 
#        devnode "*"  
 
#}  
 
#defaults {  
 
     27 #       user_friendly_names yes  
 
     28 #}  
 
 
 
5、完成之后执行如下命令发现多路径：
 
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[root@RKDB01 Server]# modprobe dm-multipath  
 
[root@RKDB01 Server]# multipath -F  
 
[root@RKDB01 Server]# multipath dm-multipath  
 
[root@RKDB01 Server]# multipath dm-round-robin  
 
[root@RKDB01 Server]# service multipathd restart  
 
正在关闭multipathd 端口监控程序：                          [确定]  
 
正在启动守护进程multipathd：                               [确定]  
 
[root@RKDB01 Server]# multipath -v2  
 
[root@RKDB01 Server]# multipath -v2  
 
[root@RKDB01 Server]# multipath -ll  
 
mpath1 (3600d02310000011b16a5d57c6a1bd99a) dm-0 TOYOU,NetStor_iSUM510  
 
[size=3.3T][features=0][hwhandler=0][rw]  
 
_ round-robin 0 [prio=2][ena bled]  
 
 _ 1:0:0:0 sdb 8:16  [failed][ready]  
 
 _ 1:0:1:0 sdc 8:32  [failed][ready]  
 
[root@RKDB01 Server]#   
 
 
 
6、重启服务器后，我们可以看到多路径信息了：
 
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[root@RKDB01 ~]# ll /dev/mapper/  
 
总计 0  
 
crw------- 1 root root  10, 60 11-05 22:35 control  
 
brw-rw---- 1 root disk 253,  0 11-05 22:35 mpath1  
 
brw-rw---- 1 root disk 253,  1 11-05 22:35 mpath2  
 
[root@RKDB01 ~]# multipath -ll  
 
mpath2 (3600d02310000011b76128b9c63138cf4) dm-1 TOYOU,NetStor_iSUM510  
 
[size=3.2T][features=0][hwhandler=0][rw]  
 
_ round-robin 0 [prio=2][active]  
 
 _ 1:0:0:1 sdc 8:32  [active][ready]  
 
 _ 1:0:1:1 sde 8:64  [active][ready]  
 
mpath1 (3600d02310000011b16a5d57c6a1bd99a) dm-0 TOYOU,NetStor_iSUM510  
 
[size=20G][features=0][hwhandler=0][rw]  
 
_ round-robin 0 [prio=2][active]  
 
 _ 1:0:0:0 sdb 8:16  [active][ready]  
 
 _ 1:0:1:0 sdd 8:48  [active][ready]  
 
 
 
7、通过fdisk 看可以生成了DM-0/DM-1两个盘，正是上面sdc/sde,sdb/sdd多路径后出来的：
 
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[root@RKDB01 ~]# fdisk -l  
 
Disk /dev/sda: 299.4 GB, 299439751168 bytes  
 
255 heads, 63 sectors/track, 36404 cylinders  
 
Units = cylinders of 16065 * 512 = 8225280 bytes  
 
   Device Boot      Start         End      Blocks   Id  System  
 
/dev/sda1   *           1          38      305203+  83  Linux  
 
/dev/sda2              39       13092   104856255   83  Linux  
 
/dev/sda3           13093       19619    52428127+  83  Linux  
 
/dev/sda4           19620       36404   134825512+   5  Extended  
 
/dev/sda5           19620       26146    52428096   83  Linux  
 
/dev/sda6           26147       28757    20972826   83  Linux  
 
/dev/sda7           28758       30324    12586896   82  Linux swap / Solaris  
 
/dev/sda8           30325       36404    48837568+  83  Linux  
 
Disk /dev/sdb: 21.4 GB, 21474836480 bytes  
 
255 heads, 63 sectors/track, 2610 cylinders  
 
Units = cylinders of 16065 * 512 = 8225280 bytes  
 
Disk /dev/sdb doesn't contain a valid partition table  
 
Disk /dev/sdc: 3568.4 GB, 3568429957120 bytes  
 
255 heads, 63 sectors/track, 433836 cylinders  
 
Units = cylinders of 16065 * 512 = 8225280 bytes  
 
Disk /dev/sdc doesn't contain a valid partition table  
 
Disk /dev/sdd: 21.4 GB, 21474836480 bytes  
 
255 heads, 63 sectors/track, 2610 cylinders  
 
Units = cylinders of 16065 * 512 = 8225280 bytes  
 
Disk /dev/sdd doesn't contain a valid partition table  
 
Disk /dev/sde: 3568.4 GB, 3568429957120 bytes  
 
255 heads, 63 sectors/track, 433836 cylinders  
 
Units = cylinders of 16065 * 512 = 8225280 bytes  
 
Disk /dev/sde doesn't contain a valid partition table  
 
Disk /dev/dm-0: 21.4 GB, 21474836480 bytes  
 
255 heads, 63 sectors/track, 2610 cylinders  
 
Units = cylinders of 16065 * 512 = 8225280 bytes  
 
Disk /dev/dm-0 doesn't contain a valid partition table  
 
Disk /dev/dm-1: 3568.4 GB, 3568429957120 bytes  
 
255 heads, 63 sectors/track, 433836 cylinders  
 
Units = cylinders of 16065 * 512 = 8225280 bytes  
 
Disk /dev/dm-1 doesn't contain a valid partition table  
 
Disk /dev/sdf: 4009 MB, 4009754624 bytes  
 
255 heads, 63 sectors/track, 487 cylinders  
 
Units = cylinders of 16065 * 512 = 8225280 bytes  
 
   Device Boot      Start         End      Blocks   Id  System  
 
/dev/sdf4   *           1         488     3915744+   b  W95 FAT32  
 
Partition 4 has different physical/logical endings:  
 
     phys=(486, 254, 63) logical=(487, 125, 22)  
 
[root@RKDB01 ~]#   
 
 
 
8、我们同时也可以在/dev/mapper目录中查看到多路径映射的信息：
 
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[root@RKDB01 ~]# ll /dev/mapper/  
 
总计 0  
 
crw------- 1 root root  10, 60 11-06 00:49 control  
 
brw-rw---- 1 root disk 253,  2 11-06 00:49 data-data001  
 
brw-rw---- 1 root disk 253,  0 11-06 00:49 mpath1  
 
brw-rw---- 1 root disk 253,  1 11-06 00:49 mpath2