Xen users - Jan 2006 - Re: FW: Xen 3: Functional NAT Possible?

Ewan Mellor wrote:
>>
>> Ian Pratt wrote:
>>>  
>>>
>>>> 	I have been trying for days now to get a working nat setup
with
>> my 
>>>> domU''s using the default nat scripts.
>>> Just look at what the demo CD does for a nice example of how to set
up
>>> NAT.
>>>
>>> Ian
>>>  
>> 	Ok, i checked that out, and it seemed to help me figure it out a
>> lot. 
>> It looks like the key i was missing was having dhcp=dhcp in my xend
>> config. Now each time a vm starts up it edits my dhcpd config and sets
>> it up for that VM and the vm gets an ip and is setup to connect to the
>> Internet. Wonderful.
>>
>> 	The problem still remains though, that each new VM i setup... or
>> even if i stop a vm and start it, it ends up with a different ip. This
>> makes the vm''s pretty useless if i want to forward ports to
the vms. I
>> always specify mac id''s for my vms:
>>
>> vif = [ ''mac=00:50:22:22:22:02'']
>>
>> if i specify an ip aswell:
>>
>> vif = [ ''mac=00:50:22:22:22:02, ip=10.0.1.2'']
>>
>> when i try to start that vm it complains something about vif 0 not
being
>> able to start
> 
> This should work -- it does for me.  Could you find out why the vif cannot
> start?  If you can''t see anything from the logs, then please use
xen-bugtool,
> which is a little application that will collate your logs in a tarball so
that
> you can send them to me.
> 
> Thanks,
> 
> Ewan.
The actual error is:

[root@dom0 ~]# xm create -c mysql
Using config file "/etc/xen/mysql".
Error: Device 0 (vif) could not be connected. Hotplug scripts not working.
[root@dom0 ~]#

the only thing that added to the logs is:


xen-hotplug.log:

/etc/xen/scripts/vif-nat: line 90: (0xFFFFFFFF << (32 - )) &
0xFFFFFFFF
: syntax error: operand expected (error token is ")) & 0xFFFFFFFF
")
xenstore-read: couldn''t read path backend/vbd/4/2050/physical-device
xenstore-read: couldn''t read path backend/vbd/4/2049/physical-device
/etc/xen/scripts/vif-nat: line 90: (0xFFFFFFFF << (32 - )) &
0xFFFFFFFF
: syntax error: operand expected (error token is ")) & 0xFFFFFFFF
")

here is my xend-config.sxp (minus comments):

(logfile /var/log/xend.log)
(loglevel DEBUG)
(xend-http-server yes)
(xend-relocation-server yes)
(xend-address localhost)
(xend-relocation-address localhost)
(network-script ''network-nat dhcp=yes'')
(vif-script     ''vif-nat dhcp=yes'')
(dom0-min-mem 160)
(dom0-cpus 0)

here is the config for the domain i was trying to start (minus comments):

kernel = "/boot/vmlinuz-2.6.12.6-xen3_2.1_fc4"
ramdisk = "/boot/initrd-2.6.12.6-xen3_2.1_fc4.img"
memory = 160
name = "mysql"
vif = [ ''mac=00:50:22:22:22:03, ip=10.0.3.2'']
nics=1
dhcp = "dhcp"
hostname="mysql.sadclown.net"
disk = [''file:/xen/mysql.img,sda1,w'',
         ''file:/xen/mysql.swap.img,sda2,w'']
root = "/dev/sda1 ro"
extra = "4"
on_reboot   = ''restart''


let me know if there is any more info you need.

-Jeff

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

This could be because of the way I build servers, but I thought I''d ask
anyway.

I have a server - intel pen4 3.0 HT, 2G ram, Raid 5 array software array.

I''m using xen 2.0.6, although the problem has happend with 2.0.0 as
well.

I tend to prefer gentoo for server, but use debian as well.  My debian 
based servers seem immune to this running out of memory issue.

Okay, so here''s the problem:
No matter how heavily loaded a gentoo server is under xen it will 
eventually run out of ram and then out of swap resulting in a crash - 
you have to watch them.  The most heavily loaded server (not really that 
bad anyway - 47G/month) requires reboots at least once a month.  I''m
not
complaining mind you, it''s just that it seems odd behavior for linux to
not release the memory and use it till it crashes.

This does not happen on my native gentoo boxes - the ones built without 
xen, nor does it happen to the domain0 running gentoo - only to the 
domainX''s

It doesn''t happen to domainX''s running debian or (1 case only)
redhat.

So.. I don''t know what''s the common cause - I don''t
use nptl when I
build the apps, although normal linux threaded is default I believe.

Perhaps this issue is resolved in xen 3.0, but alas, I don''t currently 
have a server to try it out on.

Anyway, thought I''d ask and see...
Jack

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

On Thu, Jan 05, 2006 at 01:06:14PM -0500, Jeff Utter wrote:
> Ewan Mellor wrote:
> >>
> >>Ian Pratt wrote:
> >>> 
> >>>
> >>>>	I have been trying for days now to get a working nat setup
with
> >>my 
> >>>>domU''s using the default nat scripts.
> >>>Just look at what the demo CD does for a nice example of how to
set up
> >>>NAT.
> >>>
> >>>Ian
> >>> 
> >>	Ok, i checked that out, and it seemed to help me figure it out a
> >>lot. 
> >>It looks like the key i was missing was having dhcp=dhcp in my xend
> >>config. Now each time a vm starts up it edits my dhcpd config and
sets
> >>it up for that VM and the vm gets an ip and is setup to connect to
the
> >>Internet. Wonderful.
> >>
> >>	The problem still remains though, that each new VM i setup... or
> >>even if i stop a vm and start it, it ends up with a different ip.
This
> >>makes the vm''s pretty useless if i want to forward ports
to the vms. I
> >>always specify mac id''s for my vms:
> >>
> >>vif = [ ''mac=00:50:22:22:22:02'']
> >>
> >>if i specify an ip aswell:
> >>
> >>vif = [ ''mac=00:50:22:22:22:02, ip=10.0.1.2'']
> >>
> >>when i try to start that vm it complains something about vif 0 not
being
> >>able to start
> >
> >This should work -- it does for me.  Could you find out why the vif
cannot
> >start?  If you can''t see anything from the logs, then please
use
> >xen-bugtool,
> >which is a little application that will collate your logs in a tarball
so
> >that
> >you can send them to me.
> >
> >Thanks,
> >
> >Ewan.
> 
> The actual error is:
> 
> [root@dom0 ~]# xm create -c mysql
> Using config file "/etc/xen/mysql".
> Error: Device 0 (vif) could not be connected. Hotplug scripts not working.
> [root@dom0 ~]#
> 
> the only thing that added to the logs is:
> 
> 
> xen-hotplug.log:
> 
> /etc/xen/scripts/vif-nat: line 90: (0xFFFFFFFF << (32 - )) &
0xFFFFFFFF
> : syntax error: operand expected (error token is ")) & 0xFFFFFFFF
")
> xenstore-read: couldn''t read path
backend/vbd/4/2050/physical-device
> xenstore-read: couldn''t read path
backend/vbd/4/2049/physical-device
> /etc/xen/scripts/vif-nat: line 90: (0xFFFFFFFF << (32 - )) &
0xFFFFFFFF
> : syntax error: operand expected (error token is ")) & 0xFFFFFFFF
")
This error was fixed on Dec 12, changeset 8334:b4dfb49332d2 (just after the
3.0 release).  Could you upgrade your vif-nat script and see how you get on
with that?  (You actually just have to remove the offending lines -- see 

http://xenbits.xensource.com/xen-unstable.hg?cmd=changeset;node=b4dfb49332d2935860ee8ddeebdfffcaef5e800b

HTH,

Ewan.

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users