max number of paths
 

Charlie Sharkey wrote:



Is there a maximum number of paths supported by the device mapper ?

I have a setup with 12 paths to 14 luns. I had to reduce the number of paths

to 10 for the device mapper to startup correctly.


i have seen such problems with linux kernel 2.4, long ago, when max SCSI
disk devices was 256 (and hence - also max paths for such devices).


if you're not using SCSI, but rather some other type of device - it
could be a limitation of the specific low level driver.


which kernel are you using? and which linux distribution? and what kind
of block devices do your disks reside on?


--guy

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max number of paths
 

I'm seeing this on a Suse Sles10 x86_64 system, 2.6.16.60-0.34-smp.
I have a qlogic qle2462 connected to a hp eva back end.



-----Original Message-----
From: dm-devel-bounces@redhat.com [mailto:dm-devel-bounces@redhat.com]
On Behalf Of guy keren
Sent: Monday, March 15, 2010 4:15 PM
To: device-mapper development
Subject: Re: [dm-devel] max number of paths


Charlie Sharkey wrote:
>
>
> Is there a maximum number of paths supported by the device mapper ?
>
> I have a setup with 12 paths to 14 luns. I had to reduce the number of
paths
>
> to 10 for the device mapper to startup correctly.

i have seen such problems with linux kernel 2.4, long ago, when max SCSI

disk devices was 256 (and hence - also max paths for such devices).

if you're not using SCSI, but rather some other type of device - it
could be a limitation of the specific low level driver.

which kernel are you using? and which linux distribution? and what kind
of block devices do your disks reside on?

--guy

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

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max number of paths
 

do the devices look something like /dev/sd*, or /dev/cciss/* or
something similar? if the later - it _could_ be a driver-specific issue,
and i would look for info about the specific block driver.


--guy

Charlie Sharkey wrote:

I'm seeing this on a Suse Sles10 x86_64 system, 2.6.16.60-0.34-smp.
I have a qlogic qle2462 connected to a hp eva back end.




-----Original Message-----
From: dm-devel-bounces@redhat.com [mailto:dm-devel-bounces@redhat.com]
On Behalf Of guy keren
Sent: Monday, March 15, 2010 4:15 PM
To: device-mapper development
Subject: Re: [dm-devel] max number of paths


Charlie Sharkey wrote:



Is there a maximum number of paths supported by the device mapper ?

I have a setup with 12 paths to 14 luns. I had to reduce the number of

paths

to 10 for the device mapper to startup correctly.


i have seen such problems with linux kernel 2.4, long ago, when max SCSI

disk devices was 256 (and hence - also max paths for such devices).

if you're not using SCSI, but rather some other type of device - it
could be a limitation of the specific low level driver.


which kernel are you using? and which linux distribution? and what kind
of block devices do your disks reside on?


--guy

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

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


--
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dm-devel@redhat.com
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