Operating System - HP-UX
1745806 Members
4048 Online
108722 Solutions
New Discussion

Re: Need info minor number selection

 
Karthik_Bang
Occasional Contributor

Need info minor number selection

Hi All,

 

            I have created the Volume groups usings till 0x90000 minor number. After this i tried to create Volume groups using various way of setting minor number getting control file error or else minor number not unique.

 

           Please anyone explain the minor number and  if we want to create for eg.  more than 10 volume groups. how can we set minor number and create vg.

 

Regards,

 

Karthik R

5 REPLIES 5

Re: Need info minor number selection

What is the output of

 

ll /dev/*/group

 

on the system? If this is the 10th volume group on the system, I would ahve used a minor number of 0x090000, not 0x900000 - if you are running an OS version of 11.11 or 11.23 you may be hitting the kernels "maxvgs" limit


I am an HPE Employee
Accept or Kudo
Karthik_Bang
Occasional Contributor

Re: Need info minor number selection

Hi,

 

          Please refer the below the output of my server

 

bash-4.2# ll /dev/*/group
crw-rw-rw-   1 root       sys         64 0x060000 Aug 25 12:50 /dev/clarvg/group
crw-rw-rw-   1 root       sys         64 0x020000 Aug 12 13:13 /dev/d0/group
crw-r--r--   1 root       sys         64 0x050000 Sep 15 17:00 /dev/dkvg/group
crw-rw-rw-   1 root       sys         64 0x220000 Sep 20 13:06 /dev/mirvg/group
crw-rw-rw-   1 root       sys         64 0x040000 Aug 29 15:15 /dev/rdsk/group
crw-rw-rw-   1 root       sys         64 0x090000 Sep  9 14:58 /dev/symm1/group
crw-rw-rw-   1 root       sys         64 0x080000 Aug 26 12:51 /dev/symmvg/group
crw-rw-rw-   1 root       sys         64 0x140000 Aug 29 15:17 /dev/testvg/group
crw-r-----   1 root       sys         64 0x000000 Jul 26 16:28 /dev/vg00/group
crw-rw-rw-   1 root       sys         64 0x030000 Aug 12 13:17 /dev/vg02/group
crw-rw-rw-   1 root       sys         64 0x010000 Aug 18 18:00 /dev/vg100/group

 

                 The above few volume groups has minor like 0x220000 and 0x140000. The samy way if try to set minor number like 0x550000 getting control file error. Please tell me logic behind to set the minor number or else any kernels settings needs to be changed.

Pete Randall
Outstanding Contributor

Re: Need info minor number selection

It's in hex - the next after 0x090000 would be 0x0a0000.


Pete
Torsten.
Acclaimed Contributor

Re: Need info minor number selection

Looks like a pretty mess - vg02 has minor # 0x03 and so on ... usually you start at 0x00 ... to 0x09 ... followed by 0x0a and so on - just like counting in hex works. Keep an eye of the vg_max value!

Hope this helps!
Regards
Torsten.

__________________________________________________
There are only 10 types of people in the world -
those who understand binary, and those who don't.

__________________________________________________
No support by private messages. Please ask the forum!

If you feel this was helpful please click the KUDOS! thumb below!   
James R. Ferguson
Acclaimed Contributor

Re: Need info minor number selection


@Karthik_Bang wrote:

            I have created the Volume groups usings till 0x90000 minor number. After this i tried to create Volume groups using various way of setting minor number getting control file error or else minor number not unique.

 

           Please anyone explain the minor number and  if we want to create for eg.  more than 10 volume groups. how can we set minor number and create vg.


Nebulous phrases lie "control file error" aren't helpful.  *Exactly* what command did you issue, and *exactly* what was the output or error message?

 

The minor number is the kernel's mapping of the device file within the major number driver class.

 

The fact that you have minor numbers like 0x22 shows that your kernel 'maxvgs' supports at least 0x22 +1 (or 34 +1 decimal) 'maxvgs' given that 'vg00' with a minor number of zero counts as one.

 

However, as Duncan said, you should see what your kernel 'maxvgs' value is.  Posting the release your are running is always helpful, too.  To see the maximum minor number (-1) for volume groups on your system, do:

 

# kctune maxvgs

 

Regards!

 

...JRF...