Bugs item #2528121, was opened at 2009-01-22 10:02 Message generated for change (Comment added) made by dcelso You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=893831&aid=2528121&group_id=180599 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Interface (example) Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: Diego Celso (dcelso) Assigned to: Nobody/Anonymous (nobody) Summary: Connecting a guest PC to a vlan cisco switch Initial Comment: In my case I have Debian in host and guest. The switch have two vlan networks. in total there are three nets (192.168.1.0,192.168.4.0,192.168.101.0) I am using a tap interface for share the real interface. The network configuration is hostPC ******* auto br0 iface br0 inet static address 192.168.1.10 netmask 255.255.255.0 broadcast 192.168.1.255 network 192.168.1.0 gateway 192.168.1.1 bridge_ports eth0 bridge_fd 9 bridge_hello 2 bridge_maxage 12 bridge_stp off ******* guestPC ******* auto eth0 iface eth0 inet static address 192.168.1.11 netmask 255.255.255.0 broadcast 192.168.1.255 network 192.168.1.0 gateway 192.168.1.1 auto eth0.4 iface eth0 inet static address 192.168.4.11 netmask 255.255.255.0 broadcast 192.4.1.255 network 192.168.4.0 gateway 192.168.4.1 auto eth0.101 iface eth0 inet static address 192.168.101.11 netmask 255.255.255.0 broadcast 192.168.101.255 network 192.168.101.0 gateway 192.168.101.1 The running kvm have the parametters "-net nic -net tap,ifname=tap0" The result is that the guestPC can not connet to the two vlan networks. It only can do ping to the PC connected to the network 192.168.1.0. Trying the same configuration in VirtualBox it goes very well. I think that the method that kvm use for share the interface is not a completely real share. ---------------------------------------------------------------------- >Comment By: Diego Celso (dcelso) Date: 2009-01-23 17:46 Message: Thanks to both, im using lenny package kvm, it is kvm 72. With e1000 the trouble still continue. With virtio the network is unnestable, sometimes run well and other times run bad. Now, with virtio interface. I have running two guestPC and when I connet remotely using ssh to one Guest, the other guest doesnt respond to the ping. It would be for using virtio in kvm72? And How can i verify if im using "mtu 1518"? Thanks again ---------------------------------------------------------------------- Comment By: Alex Williamson (alex_williamson) Date: 2009-01-23 00:41 Message: I've used VLANs recently with both the e1000 and virtio NICs, haven't tried with the default 8139 NIC. For e1000 you need kvm-80 or better. For virtio, turn the MTU in the guest down a little bit (1500 - 4 should do it) or you'll hit a packet truncation issue (patch on the mailing list). You also need to make sure the host NIC on the bridge is not filtering VLAN packets. This typically means it can't be part of a VLAN. ---------------------------------------------------------------------- Comment By: Dor Laor (thekozmo) Date: 2009-01-22 15:20 Message: Where is your destination machine/interface? Note that if the guest nic is a vlan, the packet should come out tagged. A vlan interface needs to receive it on the host or on remote host. You can tcpdump the bridge to make sure the packets are tagged. Also make sure the mtu is 1518 (+4 for vlan tag) It was tested in the past without any issues. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=893831&aid=2528121&group_id=180599 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html