Re: [CentOS-virt] Network and IP's

[Thomas Rønshof]

Title: sig


  
  
Thanks.

I have found the way of making a bridged network in the docs.

I will be using RH 6.0 for both host and guests, so as I read, the
KVM para-virtualized drivers are already loaded and installed.
Correct ?
Should be best for database performance.

What about PCI device assignment and SR-IOV ? Is that an issue, I
should think about ?

And guest timing management ? Isn't that for more real-time
applications ?





  
  
  
  Med venlig hilsen / Best Regards 
  
  
  

  
Thomas Rønshof
   Tel: +45 44923626 / 39551529
  Mobil:
+45 40575588 
  Mail: t...@kyborg.dk
  Web: 
  www.kyborg.dk


Den 24-09-2011 23:10, Michael Schumacher skrev:

  Thomas,


  
Ok.. thanks. Can I use virt-manager to setup a bridged-network or shall
i use the commandtool ? I also think that Cent os 5.6 used bridged as 
default...

  
  
I was using the command line. The RHEL-docs can be used for this
purpose.

You are right, Centos5 used bridged network as default. But then of
course that was a XEN-environmnet and now we have KVM. Quite a few
things work differently.

Michael

___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt


  

___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

[CentOS-virt] Packet loss between Xen machines

[Aaron Linnen]

  

We are experiencing some packet loss between xen machines which we
haven't seen before. Is this a problem anyone's run into before and/or
has ideas on how to diagnose the issue? 

The setup is CentOS 5
xen-3.0.3-80.el5_3.3 

Aaron 
  ___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

Re: [CentOS-virt] Packet loss between Xen machines

[Nehemiah]

what evidence do you have of packet loss? between the net and the machines or 
between machines bridged together with xen?

-- 
Nehemiah I. Dacres
Saint Louis University: Advanced Technology Group
Linux System Administrator 

Sent with Sparrow (http://www.sparrowmailapp.com/?sig)

On Monday, September 26, 2011 at 12:53 PM, Aaron Linnen wrote:

> We are experiencing some packet loss between xen machines which we haven't 
> seen before. Is this a problem anyone's run into before and/or has ideas on 
> how to diagnose the issue?
> 
> The setup is CentOS 5 xen-3.0.3-80.el5_3.3 
> 
> Aaron
> 
> 
> ___
> CentOS-virt mailing list
> CentOS-virt@centos.org (mailto:CentOS-virt@centos.org)
> http://lists.centos.org/mailman/listinfo/centos-virt

___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

Re: [CentOS-virt] Packet loss between Xen machines

[Aaron Linnen]

  

Pinging from one domU other domUs shows dropped packets, which is
how we initially discovered something odd was going on. It also happens
pinging to the domUs from other physical machines. 

netstat -i in dom0
shows dropped packets (TX-DRP) on the vif devices. Within the domUs it
comes back with zeros. 

It only seems to happen under fairly heavy
load. 

The machines in question are on the same bridge xen. That bridge
has separate subnets and one domU is a router that routes between them
(and performs LVS functions). 

Aaron 

On Mon, 26 Sep 2011 14:08:47
-0500, Nehemiah wrote: 

> what evidence do you have of packet loss?
between the net and the machines or between machines bridged together
with xen?
> 
> -- 
> Nehemiah I. Dacres 
> Saint Louis University:
Advanced Technology Group 
> Linux System Administrator Sent with
Sparrow [3]
> 
> On Monday, September 26, 2011 at 12:53 PM, Aaron Linnen
wrote: 
> 
>> We are experiencing some packet loss between xen machines
which we haven't seen before. Is this a problem anyone's run into before
and/or has ideas on how to diagnose the issue? 
>> 
>> The setup is
CentOS 5 xen-3.0.3-80.el5_3.3 
>> 
>> Aaron 
>> 
>>
___
>> CentOS-virt mailing
list
>> CentOS-virt@centos.org [1]
>>
http://lists.centos.org/mailman/listinfo/centos-virt [2]

 


Links:
--
[1] mailto:CentOS-virt@centos.org
[2]
http://lists.centos.org/mailman/listinfo/centos-virt
[3]
http://www.sparrowmailapp.com/?sig
___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

Re: [CentOS-virt] Packet loss between Xen machines

[Dennis Jacobfeuerborn]

Does dmesg show anything suspicious that might for example point to an 
overflowing connection tracking table or something similar?

Regards,
   Dennis

On 09/26/2011 10:17 PM, Aaron Linnen wrote:
> Pinging from one domU other domUs shows dropped packets, which is how we
> initially discovered something odd was going on. It also happens pinging to
> the domUs from other physical machines.
>
> netstat -i in dom0 shows dropped packets (TX-DRP) on the vif devices.
> Within the domUs it comes back with zeros.
>
> It only seems to happen under fairly heavy load.
>
> The machines in question are on the same bridge xen. That bridge has
> separate subnets and one domU is a router that routes between them (and
> performs LVS functions).
>
> Aaron
>
> On Mon, 26 Sep 2011 14:08:47 -0500, Nehemiah wrote:
>
>> what evidence do you have of packet loss? between the net and the
>> machines or between machines bridged together with xen?
>>
>> --
>> Nehemiah I. Dacres
>> Saint Louis University: Advanced Technology Group
>> Linux System Administrator
>> Sent with Sparrow 
>>
>> On Monday, September 26, 2011 at 12:53 PM, Aaron Linnen wrote:
>>
>>> We are experiencing some packet loss between xen machines which we
>>> haven't seen before. Is this a problem anyone's run into before and/or
>>> has ideas on how to diagnose the issue?
>>>
>>>
>>> The setup is CentOS 5 xen-3.0.3-80.el5_3.3
>>>
>>> Aaron
>>>
>>> ___
>>> CentOS-virt mailing list
>>> CentOS-virt@centos.org 
>>> http://lists.centos.org/mailman/listinfo/centos-virt
>
>
>
> ___
> CentOS-virt mailing list
> CentOS-virt@centos.org
> http://lists.centos.org/mailman/listinfo/centos-virt

___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

Re: [CentOS-virt] Packet loss between Xen machines

[Aaron Linnen]

  

Unfortunately no, not on dom0 nor on the domU that is the router
(that one did hit the conntrack limit not too long ago, so it was one of
the first things we checked). Checked dmsg and /var/log/messages on all
of the domUs and didn't see anything network or hardware related.


Aaron 

On Mon, 26 Sep 2011 22:54:55 +0200, Dennis Jacobfeuerborn
wrote: 

> Does dmesg show anything suspicious that might for example
point to an 
> overflowing connection tracking table or something
similar?
> 
> Regards,
> Dennis
> 
> On 09/26/2011 10:17 PM, Aaron
Linnen wrote:
> 
>> Pinging from one domU other domUs shows dropped
packets, which is how we initially discovered something odd was going
on. It also happens pinging to the domUs from other physical machines.
netstat -i in dom0 shows dropped packets (TX-DRP) on the vif devices.
Within the domUs it comes back with zeros. It only seems to happen under
fairly heavy load. The machines in question are on the same bridge xen.
That bridge has separate subnets and one domU is a router that routes
between them (and performs LVS functions). Aaron On Mon, 26 Sep 2011
14:08:47 -0500, Nehemiah wrote: 
>> 
>>> what evidence do you have of
packet loss? between the net and the machines or between machines
bridged together with xen? -- Nehemiah I. Dacres Saint Louis University:
Advanced Technology Group Linux System Administrator Sent with Sparrow
On Monday, September 26, 2011 at 12:53 PM, Aaron Linnen wrote: 
>>>

 We are experiencing some packet loss between xen machines which we
haven't seen before. Is this a problem anyone's run into before and/or
has ideas on how to diagnose the issue? The setup is CentOS 5
xen-3.0.3-80.el5_3.3 Aaron
___ CentOS-virt mailing list
CentOS-virt@centos.org [1] CentOS-virt@centos.org>
http://lists.centos.org/mailman/listinfo/centos-virt [2]
>>
___ CentOS-virt mailing list
CentOS-virt@centos.org [4]
http://lists.centos.org/mailman/listinfo/centos-virt [5]
> 
>
___
> CentOS-virt mailing
list
> CentOS-virt@centos.org [6]
>
http://lists.centos.org/mailman/listinfo/centos-virt [7]

 


Links:
--
[1] mailto:CentOS-virt@centos.org
[2]
http://lists.centos.org/mailman/listinfo/centos-virt
[3]
http://www.sparrowmailapp.com/?sig
[4] mailto:CentOS-virt@centos.org
[5]
http://lists.centos.org/mailman/listinfo/centos-virt
[6]
mailto:CentOS-virt@centos.org
[7]
http://lists.centos.org/mailman/listinfo/centos-virt
___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt