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So i have an issue were the drive mappings for the servers will not line up even though the configs for them match exactly.. The main problem is the path for the drives keeps switching.

foo# multipath -l
mpatha (3600507680190014da0000000000002eb) dm-0 IBM,2145
size=1.0T features='1 queue_if_no_path' hwhandler='0' wp=rw
|-+- policy='round-robin 0' prio=0 status=active
| `- 2:0:1:1 sdf 8:80  active undef running
`-+- policy='round-robin 0' prio=0 status=enabled
  `- 2:0:0:1 sdb 8:16  active undef running

So the issue i having is that dm-0 will sometimes be dm-3 which is messing the configs that i have all up is there a way to point to the alias path /dev/mapper/mpatha as opposed to pointing to /dev/dm-0 i have tried pointing it to /dev/mapper/mpatha but there is no entry in the partiton table i wasnt sure if i could just manually change the entry for dm-0 in the partition table from 

253        0 1073741824 dm-0

to 

253        0 1073741824 mapper/mpatha

Actually that will not work. Read Only file..... I'm out of ideas

Any tidbits of advice would be greatly appreciated!

ricmarques
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user316926
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  • What Linux distribution and version are you using? When you say that you manually changed the entry for dm-0 in the partition table, how did you try to do that? According, for instance, to https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/5/html/DM_Multipath/mpath_devices.html : "Any devices of the form /dev/dm-n are for internal use only and should never be used." -AND- "The devices in /dev/mapper are created early in the boot process. Use these devices to access the multipathed devices, for example when creating logical volumes." – ricmarques Oct 19 '15 at 15:37
  • I didn't i was asking if it was possible. – user316926 Oct 22 '15 at 17:39

1 Answers1

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So i resolved the issue by un-presenting the LUNS and then rescanning the scisi bus one drive at at time as they were re-presented. This was on SUSE EL12

user316926
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