Installation guide

Chapter 36. Troubleshooting
This chapter covers common problems and solutions with Red Hat Enterprise Linux virtualization.
36.1. Ident ifying available st orage and part it ions
Verify the block driver is loaded and the devices and partitions are available to the guest. This can
be done by executing "cat /proc/partitions" as seen below.
# cat /proc/partitions
major minor #blocks name
202 16 104857600 xvdb
3 0 8175688 hda
36.2. Aft er reboot ing Xen-based guest s t he console freez es
Occasionally, a Xen guest's console freezes when the guest boots. The console still displays
messages but the user cannot log in.
To fix this issue add the following line to the /etc/inittab file:
1:12345:respawn:/sbin/mingetty xvc0
After saving the file, reboot. The console session should now be interactive as expected.
36.3. Virt ualized Et hernet devices are not found by net working t ools
The networking tools cannot identify the Xen Virtual Ethernet networking card inside the guest
operation system. Verify this by executing the following (for Red Hat Enterprise Linux 4 and Red Hat
Enterprise Linux 5):
cat /etc/modprobe.conf
Or (for Red Hat Enterprise Linux 3):
cat /etc/modules.conf
The output should contain the line and a similar line for each additional interface.
alias eth0 xen-vnif
To fix this problem you will need to add the aliasing lines (for example, alias eth0 xen-vnif) for
every para-virtualized interface for the guest.
36.4. Loop device errors
If file-based guest images are used you may have to increase the number of configured loop devices.
The default configuration allows up to eight active loop devices. If more than eight file-based guests
or loop devices are needed the number of loop devices configured can be adjusted in
/etc/modprobe.conf. Edit /etc/modprobe.conf and add the following line to it:
⁠Chapt er 35. T roub leshoo t ing Xen
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