Kernel Reconfiguaration

[Ganesh Balraman]

Hi All!

I have done kernel reconfiguaration and after that my system wont boot.

I tried to boot from alternate kernel and looks ok now.But when i try to rename the backup vmunix.prev to /stand/vmunix it says both are identical and no luck.

How can we process it.

[nijokj]

if you are running with os HP-UX 11i v2/v3 (11.23/11.31)
you can load the new kernel using kconfig command
eg :kconfig -l alternateconfig

this will load the current running configuration as permanant.

[Manix]

There are better ways to boot from previous kernels , renaming wont help as there are
some soft links in /stand linking the next boot
kernel configurations , you may either change the links manually or supply arguments at the boot prompt like
ISL > /stand/vmunix.prev or /stand/backup/..

Same for IA machines, HPUX > boot vmunix.prev or other strings can be used.

Other wise you may use "kconfig' as suggested.

Thanks

Manix

[Ismail Azad · Accepted solution]

Hi ganesh balraman,

> But when i try to rename the backup vmunix.prev to /stand/vmunix it says both are identical and no luck.

I guess you would have updated your backup configuration. I duplicated your situation and it seems practically and theoretically right to have this behaviour. If you have booted from your "backup kernel", then your "backup" becomes your "current" and your /stand/current/vmunix is the same as /stand/backup/vmunix. Because of this now you will have identical configuration as your "backup" is your "current" and a backup of a backup is not maintained.

I changed the nproc value from 5003 to 4096 and booted my backup. The "current" and "backup" kernels both show 5003. I hope you get the point. That is why you say,

> But when i try to rename the backup vmunix.prev to /stand/vmunix it says both are identical and no luck.

I am guessing you have 11.11 as you have mentioned /stand/vmunix.prev but the logic remains the same.

> > I have done kernel reconfiguaration and after that my system wont boot.

Then, why trying to load that configuration if it does not boot. That is proof that someone has "poorly" tuned your "current" kernel at some point of time prob by mistake and your "backup" seems to be a clean and "nicely tuned" kernel. However, you would want to review what is in your /var/adm/kc.log. Don't forget to assign points!!

Regards
Ismail Azad

[Sajjad Sahir]

Dear Ganesh

I have done kernel reconfiguaration and after that my system wont boot.
u are right u kernel is corrupted
then u have a choice to boot the system from an alternate kernel(kernel backup)
111.But when i try to rename the backup vmunix.prev to /stand/vmunix it says both are identical and no luck. u are renaming the same name of old kernel which is corrupted, thats why u are getting such a message

thanks and regards

Sajjad

[Ganesh Balraman]

Hi Ismail!
Yes you are correct.MY OS is 11.11

Finally how to boot next time without specifying kernel name in ISL prompt?


Still not getting your point on moving my vmunix.prev kernel to /stand/vmunix.

[Ismail Azad]

Hi,

The PARISC boot loader needs the complete path of the kernel as it CANNOT traverse the /stand filesystem and find the kernel like on integrity. On 11.31 you can execute an ISL>hpux which will load the "default" kernel. For any other kernel or "named configuration" to be loaded, requires the complete path unlike on integrity. And to be honest you shouldn't be "renaming" the "default backup" kernel whether it is /stand/backup/vmunix or /stand/vmunix.prev. If you are not facing any system panics or performance problems you shouldn't be worrying about it. Please read the example of changing the nproc value in my previous post where I have mentioned a /stand/backup/vmunix would be your /stand/vmunix.prev.

Regards
Ismail Azad