OpenVZ Forum


Home » Mailing lists » Users » ARP queris being ignored
Re: ARP queris being ignored [message #29848 is a reply to message #29808] Sat, 26 April 2008 15:08 Go to previous message
chris is currently offline  chris
Messages: 5
Registered: April 2008
Junior Member
Hi Christian,

I didn't see your post on openvz-users (I only got the personally
addressed copy).  I'll address this to openvz-users.  Thanks for your
reply and ideas also.

> Try: arp -vn 
> 
> It should show a line with your VE IP address, like this:
> 
> 10.10.150.244       *    <from_interface>    MP       eth0
> 
> If you don't have such a line, the host node will not respond to ARP
> queries (except if you turn on proxy_arp, but I'd advise against 
> this).

Unfortunately things still seem wrong.  To illustrate, here's what I
get for vzlist:

[root@sonata ~]# vzlist
      VEID      NPROC STATUS  IP_ADDR         HOSTNAME                        
        10         68 running 192.168.0.10    trixbox.cgb1911.mine.nu         
       105        124 running 192.168.0.105   zimbra-ose.cgb1911.mine.nu      
       106         24 running 192.168.0.106   otrs.cgb1911.mine.nu            
       107         26 running 192.168.0.107   ipplan.cgb1911.mine.nu          
       108          6 running 192.168.0.108   freeside.cgb1911.mine.nu        
       109          8 running 192.168.0.109   enomalism.cgb1911.mine.nu       
       110         65 running 192.168.0.110   virtualmin.cgb1911.mine.nu      
       111         77 running 192.168.0.111   ispconfig.cgb1911.mine.nu       
       112         33 running 192.168.0.112   splunk.cgb1911.mine.nu          
       115         77 running 192.168.0.115   zimbra4.cgb1911.mine.nu         
       116         28 running 192.168.0.116   cacti-test.cgb1911.mine.nu      
    100001          1 running -               -                               


Now, you'd expect exactly that same number of entries in the arp
table, one for each IP.  Unfortunately, only entries for 105 and 10
exist (they are ones I've had to restart to 'make work').

[root@sonata ~]# arp -vn
Address                  HWtype  HWaddress           Flags Mask            Iface
192.168.0.221            ether   00:11:93:98:67:45   C                     eth0
192.168.0.160            ether   00:07:E9:5F:BA:60   C                     eth0
192.168.0.253            ether   00:1B:2B:2C:C3:4D   C                     eth0
192.168.0.43             ether   00:19:D1:69:FD:2E   C                     eth0
192.168.0.105            *       *                   MP                    eth0
192.168.0.10             *       *                   MP                    eth0
Entries: 6      Skipped: 0      Found: 6

> The VE start script sets this up (so a restart will fix it), but
> I've also seen cases where these entries get lost after some time.
> Haven't been able to produce a test case, though.

Yeah, I hadn't determined what triggers the problem as yet.  Some
further digging has revealed that a script:

  /usr/share/vzctl/scripts/vpsnetclean

runs every 5 minutes in cron.  It has all the characteristics of a
program that would be breaking arp entires for my running VE's.  I
just need to work out if and then why it determines a VE is 'stopped'
and calls clear_ve_net to tidy up IP/ARP entries.  Will reply if I
have anything more.

> Any chance that you are using a firewall on the host node which
> fiddles with the ARP stuff? (shorewall?)

Nope, not using anything like that.  Just standard Centos 5 base
system with OVZ kernel and management tools.

Regards,

Chris Bennett (cgb)
 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: vzmigrate (3.0.22) destroy the source, even -r no
Next Topic: Dear users@openvz.org April 89% 0FF
Goto Forum:
  


Current Time: Tue Mar 19 08:08:02 GMT 2024

Total time taken to generate the page: 0.02433 seconds