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Update and Kernel error

Update and Kernel error
« on: January 11, 2018, 11:23:05 PM »
Continuing my saga with my latest update to the server, and my inability to run the reconfigure. Customer turned server off by mistake! Great, now I cannot get it to boot at all.
At the boot console, I selected an earlier kernel, it then booted fine. Read an article on similar problems with centos, so removed the latest kernel.  And thought I could re-install the new. Did a reconfigure for good measure.
All I got was :-
kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
Pid: 1, comm: swapper Not tainted 2.6.32-696.10.2.el6.i686 #1
Call Trace:

Ran the recover CD and manged to follow instruction for re-installing grub. It seemed to work ?
But now I get :-VFS: Cannot open root device "Mapper/" or unknown-block(0,0)

I am at a loss now, this is as far as my recovery knowledge goes. I assume that I need to get a working kernel back? Oh and to add insult to injury this is on a VM, so not that easy to cut and past the screen info.

Any help desperately welcome

Paul.


Infamy, Infamy, they all have it in for me!

Offline Jean-Philippe Pialasse

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Re: Update and Kernel error
« Reply #1 on: January 12, 2018, 03:41:29 AM »
Have tou tried booting on the previous kernel ?

Online Stefano

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Re: Update and Kernel error
« Reply #2 on: January 12, 2018, 09:11:42 AM »
is your SME running as a XEN VM?
and with the latest available kernel?

If so, get your last (and good)backup, reinstall and restore
Consulente di Smeserver.it -  Soluzioni e supporto su Sme server in Italia

Re: Update and Kernel error
« Reply #3 on: January 12, 2018, 12:33:57 PM »
Have tou tried booting on the previous kernel ?

Sadly when I removed the troublesome kernel, it somehow deleted all the others, as well as stopping the one I thought was OK booting.
Infamy, Infamy, they all have it in for me!

Re: Update and Kernel error
« Reply #4 on: January 12, 2018, 12:37:07 PM »
is your SME running as a XEN VM?
and with the latest available kernel?

If so, get your last (and good)backup, reinstall and restore
That actually brings me onto another point. I was not getting any notifications from the server that the backup had actually failed! My own fault of course for not actually checking, I usually rely on an email from the server to establish this.

Is there a way to restore email over the top of new emails that may have arrived? Will the restore process delete or keep what is in the folders maildir?  Again, I set the restore off last night, I can see that some email managed to come in. It was rather late and I should have just pulled it from the internet, but was rather tired.

Paul.
Infamy, Infamy, they all have it in for me!

Re: Update and Kernel error
« Reply #5 on: January 13, 2018, 02:06:25 AM »
is your SME running as a XEN VM?
and with the latest available kernel?

If so, get your last (and good)backup, reinstall and restore

Stefano: WHY???  Is it that far gone?  Has he blown out all hope of booting a working kernel??

While true, kernel 2.6.32-696.18.7.el6 borks SME in a XEN VM, booting into Rescue Mode with the install media and using the CLI to change grub.conf to use the previous kernel will bring your server back up.  Uninstall the new kernel and all will be right in the world.

Drifting:  If you started a restore over top of your existing install and not a crisp and clean install (the recommended procedure), you might be in for a mess...  I hope for the best, but you should expect an unstable state after the restore completes.  If it was a fresh install, the emails would never have been received since no accounts existed (refused due to nonexistent accounts).

« Last Edit: January 13, 2018, 02:10:15 AM by NTILZA »

Offline ReetP

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Re: Update and Kernel error
« Reply #6 on: January 13, 2018, 09:34:34 AM »
Probably should have booted in rescue mode and checked which, if any, kernels were left installed.

The original error, if searched, suggests a missing or borkrd initrd image.

The fix was probably to mount the drive chroot and reinstall some kernels.

From the sounds of things now it has probably gotten a bit messy. Restore should have been done with the box/vm disconnected. Once restored then enable net access and most of your new mail should arrive having been held by other servers.

Hope you have it sorted.
...
1. Read the Manual
2. Read the Wiki
3. Don't ask for support on Unsupported versions

Bugs are easier than you think: http://wiki.contribs.org/Bugzilla_Help

If you love SME and don't want to lose it, join in: http://wiki.contribs.org/Koozali_Foundation

Re: Update and Kernel error
« Reply #7 on: January 13, 2018, 07:09:46 PM »
Probably should have booted in rescue mode and checked which, if any, kernels were left installed.

The original error, if searched, suggests a missing or borkrd initrd image.

The fix was probably to mount the drive chroot and reinstall some kernels.

From the sounds of things now it has probably gotten a bit messy. Restore should have been done with the box/vm disconnected. Once restored then enable net access and most of your new mail should arrive having been held by other servers.

Hope you have it sorted.

Hi, to fill you in, yes I would have probably been best to check what kernels were actually there. What I could not understand at the time, was my deleting the latest kernel would affect the rest? Hindsight is a wonderful thing. Anyway all was not lost, built a new VM (ESXi) with a clean install of 9.2, did a restore from last known good backup. Used a program called pmagic (Linux desktop with recovery tools) and mounted the none bootable drive, with network access. FTP'd the missing files and emails, sorted out the permissions on the email and ebays, and all was good with the world.
Thanks for the help and advice.

Paul.
Infamy, Infamy, they all have it in for me!

Offline ReetP

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Re: Update and Kernel error
« Reply #8 on: January 14, 2018, 01:02:05 PM »
Hi, to fill you in, yes I would have probably been best to check what kernels were actually there. What I could not understand at the time, was my deleting the latest kernel would affect the rest? Hindsight is a wonderful thing.

Hard to tell without actually seeing what you typed :-)

Possibly you removed a working one and left the corrupted one in place, or removed the corrupted one but it didn't properly generate grub/initrd for the current one or something when it uninstalled.

Quote
Anyway all was not lost, built a new VM (ESXi) with a clean install of 9.2, did a restore from last known good backup. Used a program called pmagic (Linux desktop with recovery tools) and mounted the none bootable drive, with network access. FTP'd the missing files and emails, sorted out the permissions on the email and ebays, and all was good with the world.
Thanks for the help and advice.

Glad you got it sorted :-)
...
1. Read the Manual
2. Read the Wiki
3. Don't ask for support on Unsupported versions

Bugs are easier than you think: http://wiki.contribs.org/Bugzilla_Help

If you love SME and don't want to lose it, join in: http://wiki.contribs.org/Koozali_Foundation

Re: Update and Kernel error
« Reply #9 on: January 14, 2018, 01:05:26 PM »
Actually, seems I have done something else wrong, might be permission on the mail folders, but have not had any mail since I copied over the new mail messages. Any idea what the permissions should be for the user and maildir subfolder?
Admin still works fine.

Trying to find if there is some way to restore the default rights for the user folders. I have also just loaded up qmhandle and can see email in the queue, so not sure what has happened now. Getting a bit desperate, anyone any idea?

Regards Paul.
« Last Edit: January 14, 2018, 02:12:07 PM by Drifting »
Infamy, Infamy, they all have it in for me!

Offline Jean-Philippe Pialasse

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Re: Update and Kernel error
« Reply #10 on: January 15, 2018, 08:57:05 PM »
Actually, seems I have done something else wrong, might be permission on the mail folders, but have not had any mail since I copied over the new mail messages. Any idea what the permissions should be for the user and maildir subfolder?
Admin still works fine.

Let's say for user jppialasse, Maildir folder and dot-qmail files
Code: [Select]
drwxr-xr-x  79 jppialasse jppialasse 16384 15 janv. 20:26 Maildir
-rw-r--r--   1 jppialasse jppialasse   594  2 janv.  2017 .qmail
lrwxrwxrwx   1 jppialasse jppialasse     6 20 juil.  2014 .qmail-default -> .qmail
-rw-r--r--   1 jppialasse jppialasse   482 17 sept.  2007 .qmail-junkmail

and its content
Code: [Select]
drwxr-xr-x 2 jppialasse jppialasse  65536 15 janv. 20:21 cur
drwxr-xr-x  5 jppialasse jppialasse   4096 14 nov.  14:55 .subdir
drwxr-xr-x  2 jppialasse jppialasse   4096 15 janv. 20:01 new
drwxr-xr-x  2 jppialasse jppialasse   4096 15 janv. 20:21 tmp


Trying to find if there is some way to restore the default rights for the user folders. I have also just loaded up qmhandle and can see email in the queue, so not sure what has happened now. Getting a bit desperate, anyone any idea?

Regards Paul.

Re: Update and Kernel error
« Reply #11 on: February 21, 2018, 02:29:43 PM »
Rude of me, but I have had a few medical problems and have not really been back here since.

But would just like to thank those who helped me resolve the issues I had with this server, without your help I would have been lost!

Thank you all again, you are stars!

Paul.
Infamy, Infamy, they all have it in for me!

Online Stefano

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Re: Update and Kernel error
« Reply #12 on: February 21, 2018, 03:29:41 PM »
you are welcome ;-)
hope everything is ok
Consulente di Smeserver.it -  Soluzioni e supporto su Sme server in Italia