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Hey, I have a problem with xen networking. I'm using centos 5.5 64bit, and have installed xen 3.4 from gitco (unofficial) repository, along with libvirt and xen-tools. I got it previously working on official xen (3.2 iirc) without much of a hassle - I believe network just worked in default settings, with bridged settings (given that I provide= mac address for guest adapter that hetzner - my hoster - set up for me for my additional ip, my guest windows os will just found dhcp server and all will work automagically).

However, now I can't get it to work. If I leave default network-bridge xen settings enabled, my dom0 instantly gets down after reboot or xend restart. I don't really know what happens, since the only way to get my server back is to reboot it...

I've also tried routed setup, but I did not work after a few hours of struggling to set it up properly, so I eventually gave up, as it seems to be more challenging setup... so I'd rather try to get bridged attempt to work.

The settings in xend.sxp I want to use are:

(network-script network-bridge)
(vif-script vif-bridge)

Here is my ifconfig if I comment out everything network-related in xend.sxp along with the ifconfig after starting the network-bridge (i.e. there is already no connectivity when it happens - I've dumped it to the file): - is the Bcast of normal for the already-virtual eth0?

I've tried running the network script by hand to see what will happen:

cd /etc/xen
./network-bridge start; ./network-bridge stop

but no luck, it still goes down somewhere in the process and doesn't go back - restarting is the only way to get my server back.


bash -xv ./network-bridge start 2>&1 | tee out.txt

gave me this output: . Interestingly, the last line in ssh wasn't always the same: it would sometimes show up to the 305th line of the paste:


the other it would stop at 530th line:

+ ip link show peth0

Still, I don't know wha could I make out of it or what else should I try?

Sorry for the lengthy description. I would appreciate all kind of suggestions.

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What does XEN 3.4 give you that the stock XEN in CentOS doesn't? If your config works under stock - then I would suggest running that. At least your production environment stays online working. – Mister IT Guru Apr 20 '11 at 21:14
Unfortunately, xen version 3.4 is the first to be able to virtualize windows server 2k8 r2, which I intend to use... – trakos Apr 20 '11 at 22:49
Hey! Finally, I got it working! I just copied the whole /etc/xen/scripts directory from the xen 3.2 that worked and voila! Everything's working as it should. Thanks for the help, you pointed me into the right direction :) – trakos Apr 21 '11 at 0:14
up vote 1 down vote accepted

Hey! Finally, I got it working! I just copied the whole /etc/xen/scripts directory from the xen 3.2 that worked and voila! Everything's working as it should. As simple as:

mkdir xen303
cd xen303
rpm2cpio xen-3.0.3-105.el5.x86_64.rpm  | cpio -idv
mv /etc/xen/scripts /etc/xen/scripts.bak
cp -pR xen303/etc/xen/scripts /etc/xen/scripts
rm -R xen303

and it looks like all the scripts are compatible with xen3.4, while working without further tweaking :)

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