UDEV 如何设置MULTIPATH出来的盘？

武汉-SSH

使用MULTIPATH，如何配置UDEV。。。。。

mpath0 (2001738000ee70076) dm-2 IBM,2810XIV
[size=752G][features=1 queue_if_no_path][hwhandler=0][rw]
\_ round-robin 0 [prio=2][active]
\_ 0:0:0:1 sda 8:0   [active][ready]
\_ 1:0:0:1 sdb 8:16  [active][ready]

[root@cwdb ~]# scsi_id -g -s /block/sda
2001738000ee70076
[root@cwdb ~]# scsi_id -g -s /block/sdb
2001738000ee70076

Maclean Liu(刘相兵

ODM Data:

Configuring raw devices (multipath) for Oracle Clusterware 10g Release 2 (10.2.0) on RHEL5/OEL5 [ID 564580.1]
Multipath, Raw and Udev
The necessity for high availability access to storage is well understood. For singlepath environments, raw devices can easily be configured via udev rules as described in Note.465001.1. For multipath environments, however, configuration of raw devices against multipathed devices via udev is more complex. In fact, significant modification of default udev rules can introduce issues with supportability. Therefore, other means are recommended to achieve configuration of raw devices against multipathed devices with multipath device naming persistency.


udev 配置multipath 规则会复杂一些，udev甚至自带了multipath的规则：

1. [oracle@vrh2 rules.d]$ cat /etc/udev/rules.d/40-multipath.rules
   
2. # multipath wants the devmaps presented as meaninglful device names
   
3. # so name them after their devmap name
   
4. SUBSYSTEM!="block", GOTO="end_mpath"
   
5. RUN+="socket:/org/kernel/dm/multipath_event"
   
6. # KERNEL!="dm-[0-9]*", ACTION=="add", PROGRAM=="/bin/bash -c '/sbin/lsmod | /bin/grep ^dm_multipath'", RUN+="/sbin/multipath -v0 %M:%m"
   
7. KERNEL!="dm-[0-9]*", GOTO="end_mpath"
   
8. PROGRAM!="/sbin/mpath_wait %M %m", GOTO="end_mpath"
   
9. PROGRAM!="/sbin/dmsetup info -c --noheadings -j %M -m %m", GOTO="end_mpath"
   
10. RESULT!="*:*:*:*:*:*:*:mpath-*", GOTO="kpartx_check"
    
11. PROGRAM=="/sbin/dmsetup info -c --noheadings -o name -j %M -m %m", RESULT=="?*",NAME="%k", SYMLINK="mpath/%c", RUN+="/bin/bash -c '/sbin/mpath_wait /dev/mapper/%c; /sbin/kpartx -a -p p /dev/mapper/%c'"
    
12. OPTIONS="last_rule"
    
13. LABEL="kpartx_check"
    
14. RESULT!="*:*:*:*:*:*:*:part*-mpath-*", GOTO="end_mpath"
    
15. PROGRAM=="/sbin/dmsetup info -c --noheadings -o name -j %M -m %m", RESULT=="?*", NAME="%k", SYMLINK="mpath/%c"
    
16. OPTIONS="last_rule"
    
17. LABEL="end_mpath"

复制代码

也可以参考以下链接：

http://www.ardentperf.com/2008/0 ... udev-and-multipath/