Re: [dm-devel] md_component_detection = 1

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



All I can comment is LVM over the multipath implementation from Alasdair, RedHat.

For that, you need to set in /etc/lvm/lvm.conf :

scan = [ "/dev", "/dev/mapper" ] (you may or may not need this one, depending on your distro)
   filter = [ "r/sd.*/", "a/.*/" ]
   types = [ "device-mapper", 254 ]

Here the 254 may vary depending on your setup. To find out for your case, do :

[root@cl039 root]# grep mapper /proc/devices
254 device-mapper

Then everything should work as expected :

[root@cl039 root]# multipath -l -v2
red (3600a0b80000b596a000003113d9c5381)
[size=33 GB][features="0"][hwhandler="0"]
\_ round-robin 0 [enabled][first]
 \_ 4:0:3:9 sdan 66:112  [ready ][active]
 \_ 5:0:1:9 sdbh 67:176  [ready ][active]
\_ round-robin 0 [enabled]
 \_ 5:0:3:9 sdcb 68:240  [ready ][active]
 \_ 4:0:1:9 sdt  65:48   [ready ][active]

[root@cl039 root]# pvcreate /dev/mapper/red
 Physical volume "/dev/mapper/red" successfully created

[root@cl039 root]# pvscan
 PV /dev/mapper/red         lvm2 [33.86 GB]
 Total: 1 [33.86 GB] / in use: 0 [0   ] / in no VG: 1 [33.86 GB]


That's the more precise info I can share onn the subject.
Now your on your own.

Regards,
cvaroqui


shahid shaikh wrote:


Hello Chris,

   I have written a sample psuedo driver which is basically consolidating
multiple paths to LUNs.
So I need prevent SCSI devices from scanning.

I gone thro' lvm.conf and found out that md is doing the similar thing by
setting following value in lvm.conf

        md_component_detection = 1
this parameter, if set, prevents scanning of all the SCSI devices
contributed in the creation of md.

So is there any parameter in LVM2 or device mapper, setting or clearing
which can prevent scanning of SCSI devices used for my psuedo driver.
Obviously other than filtering it out.

Thanks and Regards,
Shahid Shaikh.
Software Engineer.



http://www.patni.com
World-Wide Partnerships. World-Class Solutions.
_____________________________________________________________________

This e-mail message may contain proprietary, confidential or legally
privileged information for the sole use of the person or entity to
whom this message was originally addressed. Any review, e-transmission
dissemination or other use of or taking of any action in reliance upon
this information by persons or entities other than the intended
recipient is prohibited. If you have received this e-mail in error
kindly delete  this e-mail from your records. If it appears that this
mail has been forwarded to you without proper authority, please notify
us immediately at netadmin@xxxxxxxxx and delete this mail. _____________________________________________________________________
------------------------------------------------------------------------

--

dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel




[Index of Archives]     [DM Crypt]     [Fedora Desktop]     [ATA RAID]     [Fedora Marketing]     [Fedora Packaging]     [Fedora SELinux]     [Yosemite Discussion]     [KDE Users]     [Fedora Docs]

  Powered by Linux