[CentOS-virt] Having trouble starting more than 8 Xen guests
Scot P. Floess
sfloess at nc.rr.com
Sun Sep 18 12:13:16 EDT 2011
I've spent quite a few hours trying to figure this out to no avail... I
have two machines and the result is the same on both. Additionally,
each machine does not support full hardware virtualization...
I am able to create 8 VMs. When attempting to create ninth VM, I get the following
Error: Device 51712 (vbd) could not be connected. /etc/xen/scripts/block
failed; error detected.
To create the VMs, I use the command:
"xm create [vm name]"
My machine has 8 GB RAM and is an "old school" dual opteron box.
"uname -a" is:
Linux centos-host-2 2.6.18-274.3.1.el5.centos.plusxen #1 SMP Wed Sep 7
06:25:54 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux
To be clear, I can shutdown any one of the 8 VMs and then run the ninth
"xm create" - that VM will start...
I did some google'ing and from what I cn tell that error arises due to the
lack of loop back devices (there being 8 by default)...
I've tried both using MAKEDEV (in my /etc/rc.local) to create a number of
loop back devices and put max_loops in my grub,.conf file. For example
here is what I have in grub.conf now:
title CentOS (2.6.18-274.3.1.el5.centos.plusxen)
module /vmlinuz-2.6.18-274.3.1.el5.centos.plusxen ro root=LABEL=/
Due to wrapping, max_loop is actually on the module /vmlinuz- line...
I also tried to put max_loop on the kernel line as well...
As I mentioned above, I also created the loop back devices from
/etc/rc.local like so:
/sbin/MAKEDEV -d /dev -m 64 loop
And, once I can log in to the machine, I do see everything in /dev (for
example /dev/loop0 to /dev/loop64)
Has anyone else had this problem? If so, how did you resolve it????
Thanks ahead of time!!!!!
Scot P. Floess RHCT (Certificate Number 605010084735240)
Chief Architect FlossWare http://sourceforge.net/projects/flossware
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