to dmp or not to dmp?

to dmp or not to dmp?

Post by J&J Guzma » Wed, 20 Mar 2002 19:40:07



We are setting up a san with an IBM Fastt 500 at my shop and my vendor says
that I should use IBM's multipath driver instead of Veritas volume manager
dmp, but doesn't really give me a reason.  Any suggestions on which I should
use and why?

thanks!

 
 
 

to dmp or not to dmp?

Post by Pau » Thu, 21 Mar 2002 09:42:56



> We are setting up a san with an IBM Fastt 500 at my shop and my vendor says
> that I should use IBM's multipath driver instead of Veritas volume manager
> dmp, but doesn't really give me a reason.  Any suggestions on which I should
> use and why?

> thanks!

If you use VxVM 3.2 you cannot disable DMP. It is not allowed. I can't
remember if you can disable DMP with VxVM 3.1.1 but I don't think so.
You can disable DMP with VxVM 3.0. I've done it in our environment and
it works fine.  I don't have any experience with IBM Fastt so I can't
tell you why they want you to disable DMP. In our case the version of
ATF we run is not compatible with DMP. We are still waiting for an
upgraded version of ATF so that we can upgrade VxVM on that server.
If DMP is not compatible with IBM Fastt 500 using IBM's multipath
driver don't go beyond VxVM 3.0.

 
 
 

to dmp or not to dmp?

Post by Jean Dio » Thu, 21 Mar 2002 09:47:23



Quote:> We are setting up a san with an IBM Fastt 500 at my shop and my vendor
says
> that I should use IBM's multipath driver instead of Veritas volume manager
> dmp, but doesn't really give me a reason.  Any suggestions on which I
should
> use and why?

> thanks!

DMP is not certified with Fastt500  (StorageTek/LSI  box) and will not work.
Depending the OS (Solaris I guess) you have to use RDAC (Redundant Dual
Access Controller) that usually comes with your disk controller SANtricity.
Under normal installation it should be under /etc/raid/bin and you should
have a file call rdac.*  under /etc/raid.

DMP can co-exist with RDAC.  Check the installation manual on DMP and RDAC
for special requirements.  I have several Veritas Cluster installed on
Solaris with DMP and RDAC.  My DMP is used for the D10000 boot disk failover
and RDAC for our StorageTek 9176's.  Because of the complexity of our
clusters (6 nodes) we avoid using SAN boot disk.

Jean Dion Tools & Programs
http://pages.infinit.net/dbtek/

 
 
 

1. VERITAS DMP : DMP path failures

Hello

We are running the following configuration

SF4800
Solaris 8
VRTSvxfs 3.4,REV=GA03
VRTSvxvm 3.1.1,REV=01.30.2001.22.21

The system is connected with two paths to the Storage Area Network
and we enabled VERITAS DMP in order to use the two paths.

The system has been in service for at least two years without any
problems.

Now we got the following messages in /var/adm/messages :

(..)

Nov 13 13:58:14 sun31 scsi: [ID 107833 kern.warning] WARNING:

Nov 13 13:58:14 sun31   offline
Nov 13 13:58:14 sun31 vxdmp: [ID 619769 kern.notice] NOTICE: vxdmp:
Path failure on 32/0x2c14
Nov 13 13:58:14 sun31 vxdmp: [ID 997040 kern.notice] NOTICE:
vxvm:vxdmp: disabled path 32/0x2c10 belonging to the dmpnode 227/0x3f0
Nov 13 13:58:14 sun31 scsi: [ID 107833 kern.warning] WARNING:

Nov 13 13:58:14 sun31   transport rejected (-2)
Nov 13 13:58:14 sun31 scsi: [ID 107833 kern.warning] WARNING:

Nov 13 13:58:14 sun31   offline
Nov 13 13:58:14 sun31 vxdmp: [ID 619769 kern.notice] NOTICE: vxdmp:
Path failure on 32/0x2c2c
Nov 13 13:58:14 sun31 vxdmp: [ID 997040 kern.notice] NOTICE:
vxvm:vxdmp: disabled path 32/0x2c28 belonging to the dmpnode 227/0x408

(..)

As there are so many entries at the same time stamps, I
do not see which one of a LUN's two SAN - paths actually was
temporarely
interrupted.

# format

(..)  

     205. c4t13d86 <HITACHI OPEN-9 cyl 10014 alt 2 hd 15 sec 96>

     206. c4t13d87 <HITACHI OPEN-9 cyl 10014 alt 2 hd 15 sec 96>

     207. c4t13d88 <HITACHI OPEN-9 cyl 10014 alt 2 hd 15 sec 96>

     208. c4t13d89 <HITACHI OPEN-9 cyl 10014 alt 2 hd 15 sec 96>

(..)

Question :

How can I figure out the name of the LUN (e.g. c4t13d87 )unter
<format>
which has lost one of its two DMP-paths according the messages

<vxvm:vxdmp: disabled path 32/0x2c28 belonging to the dmpnode
227/0x408>

?

I thank you for your efforts

Stefan Schmid

2. Running X Apps on a seperate box

3. 6120 (T4) with Solaris 8 and VxVM 3.2: DMP not working

4. GNOME applets processes and port connection

5. how to check free disksize with veritas DMP enabled

6. Changing Hostnames

7. Can one see if all disk controllers are equally utilized in DMP?

8. syslog on remote host

9. GDB 4.16 under glibc2.05 -> core dmp

10. parallel port device name for a DMP epson LQ 500

11. VxVM 2.5: Adding disks: DMP question

12. Veritas VM dmp & Solaris 8

13. Printing on a Tandy DMP-2100 need help!!