Linux Persistent Binding Feature

[loco_vikide]

Could anynone please elaborate on Linux Persistent Binding Feature. What are the main functionalities? What are the pros and cons of enabling it?

Thx.
Chris

[skt_skt]

There is a "persistent binding" at the storage level? What is your scenario exactly..

[loco_vikide]

Hi Santhosh Kumar Theyyan,
Thank you for replying. My question revolves around storage. I am experiencing some sporadic inconsistent queried info on storage devices. Pseudo device names change quite often. I am not using Linux Persistent Binding feature and looking into using it to fix my issues.
Regards,
Chris.

[skt_skt]

which storage(EMC)?which Linux version?
when do a see the change? after a reboot of the host or which ever is applicable in your case..so further information required to help you

[dirk dierickx · Accepted solution]

you can do this with udev, there you can specify rules for which devices should have which /dev entry.

all information is included in the manpages - man udev

[Ivan Ferreira]

For exact information please see:

http://www.redhat.com/docs/manuals/enterprise/RHEL-5-manual/Virtualization-en-US/ch-virt-lun-persistence.html

Don't forget to assign points to the answers you get. For information about this please also see:

http://forums1.itrc.hp.com/service/forums/helptips.do?#28

[loco_vikide]

Thank you very much for the info that all of you have sent. It is very useful. Cheers.

Chris

[skt_skt]

see the binding for DM devices

root [/sbin]cat /var/lib/multipath/bindings
# Multipath bindings, Version : 1.0
# NOTE: this file is automatically maintained by the multipath program.
# You should not need to edit this file in normal circumstances.
#
# Format:
# alias wwid
#
mpath0 350060160b060352550060160b0603525
mpath1 3600601607237160055901448f2b5da11
mpath2 360060160723716002203af5cd2f1db11
mpath3 36006016072371600c9568c2171c9da11
mpath4 3600601607237160080abebebd593dc11
mpath5 360060160723716008ec7259dedd4dc11

root [/dev/mpath]ll
total 0
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath1 -> ../dm-37
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath10 -> ../dm-45
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath11 -> ../dm-46
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath2 -> ../dm-38
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath4 -> ../dm-39
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath5 -> ../dm-40
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath6 -> ../dm-41
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath7 -> ../dm-42
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath8 -> ../dm-43
lrwxrwxrwx 1 root root 8 Feb 19 23:57 mpath9 -> ../dm-44