networking problems between vms

Hello,

I'm running 4 virtual machines on one host, connected by a network bridge on the host (IP 192.168.0.1). All TAP devices get added to that bridge when starting the vm:

brctl show

bridge name     bridge id               STP enabled     interfaces
br0             8000.52fd3fbd954e       no              tap01
                                                         tap02
                                                         tap03
                                                         tap04

I use virtio networking (but tried the e1000 driver, too). The vms have static IPs 192.168.0.250 - 253 with 192.168.0.1 as the gateway. Connecting from the host to the machines and from the machines to the internet works just fine. The problem lies in connecting from one machine to another. There is a 30 seconds delay until the connection gets established, I tried ssh, http and mysql. After the connection is there, the speed seems to be normal.

Any hints would be appreciated.

Quoted 21 lines · Volker Cordes

Hello,

I'm running 4 virtual machines on one host, connected by a network bridge on the host (IP 192.168.0.1). All TAP devices get added to that bridge when starting the vm:

brctl show

bridge name     bridge id               STP enabled     interfaces
br0             8000.52fd3fbd954e       no              tap01
                                                         tap02
                                                         tap03
                                                         tap04

I use virtio networking (but tried the e1000 driver, too). The vms have static IPs 192.168.0.250 - 253 with 192.168.0.1 as the gateway. Connecting from the host to the machines and from the machines to the internet works just fine. The problem lies in connecting from one machine to another. There is a 30 seconds delay until the connection gets established, I tried ssh, http and mysql. After the connection is there, the speed seems to be normal.

Quoted 2 lines

Any hints would be appreciated.

Does

brctl setfd br0 0.5

help?

Quoted 23 lines · Avi Kivity<avi<at> redhat.com> writes:

Quoted 21 lines · Volker Cordes

Hello,

I'm running 4 virtual machines on one host, connected by a network bridge on the host (IP 192.168.0.1). All TAP devices get added to that bridge when starting the vm:

brctl show

 bridge name     bridge id               STP enabled     interfaces
 br0             8000.52fd3fbd954e       no              tap01
                                                          tap02
                                                          tap03
                                                          tap04

I use virtio networking (but tried the e1000 driver, too). The vms have static IPs 192.168.0.250 - 253 with 192.168.0.1 as the gateway. Connecting from the host to the machines and from the machines to the internet works just fine. The problem lies in connecting from one machine to another. There is a 30 seconds delay until the connection gets established, I tried ssh, http and mysql. After the connection is there, the speed seems to be normal.

Quoted 9 lines

Quoted 2 lines

Any hints would be appreciated.

Does

brctl setfd br0 0.5

help?

No does not help. The bridge is created in /etc/network/interfaces (debian):

iface tap0 inet manual
auto br0
iface br0 inet static

   bridge_ports          tap0
   bridge_stp            off
   bridge_maxwait        0
   bridge_fd             0

address 192.168.0.1
netmask 255.255.255.0

I'm using kvm version:
QEMU emulator version 0.13.0 (qemu-kvm-0.13.0 Debian 0.13.0+dfsg-2), Copyright
(c) 2003-2008 Fabrice Bellard
with kvm_intel

on kernel:
Linux example.com 2.6.32-5-amd64 #1 SMP Wed Jan 12 03:40:32 UTC 2011 x86_64 GNU/Linux

I also tried -no-kvm, -no-kvm-irqchip and -no-kvm-pit. Didn't help.

Even connecting to the local machine has this 30 seconds delay (only if I use 192..., localhost is ok)

Check reverse dns resolution and firewall rules. Don't seem to be a kvm problem.