Bug 1118956

Description of problem:

1. dm-setup was not able to find some directories, so dracut made an emergency stop to shell.

2. after booting from cd and manually setting grub to boot the old kernel, the next reboot with the last working kernel did not work either:

the boot messages showed something like 

"Systemd I/O error on xvda, sector 0"

and that he can't mount lvm...home.device due to timeout problems.

The mentioned systemd file is not inside/usr/lib/systemd nor /etc/systemd

e2fsck did not find any problem onthe lvm mounted filesystems,
no more IO Error messages while the server is running so far.

I doubt, that the ioerror exists. 


Jul 12 10:22:39 c1 systemd-logind[539]: New session 8 of user root.
Jul 12 10:23:01 c1 systemd[1]: Job dev-mapper-vg_s1\x2dlv_home.device/start timed out.
Jul 12 10:23:01 c1 systemd[1]: Timed out waiting for device dev-mapper-vg_s1\x2dlv_home.device.
Jul 12 10:23:01 c1 systemd[1]: Dependency failed for File System Check on /dev/mapper/vg_s1-lv_home.
Jul 12 10:23:01 c1 systemd[1]: Job dev-mapper-vg_s1\x2dlv_swap.device/start timed out.
Jul 12 10:23:01 c1 systemd[1]: Timed out waiting for device dev-mapper-vg_s1\x2dlv_swap.device.
Jul 12 10:23:01 c1 systemd[1]: Dependency failed for /dev/mapper/vg_s1-lv_swap.

the lvm seems to be ok, the partion seems to be ok too.
I could mount it manually without any problems.

3. something very wired happend afterwards.

I wanted to start SSHD to use a better shell, but instead of just starting sshd, the entire system got up to "normal" operations.

"systemctl start sshd" was used, 
the cpu got 100% , 
the loginshell did not react anymore 
and suddenly the system was booted to multiuser.target as it should have.

 With one exception: polkitd was started. It was disabled for years! now. 


QUESTIONS: 

1. How to restore the LVM to a working, reliable state again ?
2. How to find out, what caused the timeout ?
3. How to find out more about the ioerror ?


BTW: there must be a user friendlier way to switch kernels in such a situation. This particular server was running as a vm, so luckily booting from cd via vnc is possible. Telling dracut to change grub to another kernel would be mega helpful.