[ovirt-users] vlan tagging issue

[Tom Gamull]

Can you eliminate the switch or port config as the issue?  I’m a little unclear as to how you configured the nodes I have basically use a single NIC (some are LACP bonds) with a GENERAL link type (not TRUNK or ACCESS) where there is a default VLAN (which I don’t tag) and the rest of the VLANs are tagged.  On my switch (TP-LINK) I have to go to the VLANs and say TAG on all of them except the DEFAULT one.  I couldn’t get TRUNK working even with one untagged and the rest tagged. For me, using GENERAL was the way I did it.

I’m not a networking except on hardware but this discussion may clarify.  I have no idea why TRUNK didn’t work over GENERAL and didn’t spend much more time than that but here’s a discussion on the topic https://supportforums.cisco.com/discussion/11897946/general-vs-trunk-mode <https://supportforums.cisco.com/discussion/11897946/general-vs-trunk-mode>

Tom

> On Sep 14, 2016, at 3:08 PM, cmc <iucounu at gmail.com> wrote:
> 
> Hi,
> 
> I have modified my VM network to have multiple tagged networks. It used to be an untagged network and it worked fine, but I needed to add more networks on the host. The switch it is connected to has the port configured as a trunk port with these VLANs. When a VM sends traffic out (to get a DHCP address for instance), it reaches the server but does not get the DHCP offer that the server sends. I did a tcpdump on the node that hosts the VM and the packets going out do not have a VLAN tag. I assume the VM host interface would should not have the tag present, but that the  p2p1.91 interface should put the VLAN tag on.
> 
> The relevant interface configuration on the node that the VM host is on looks like:
> 
> 27: sohonet_DMZ: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP
>     link/ether a0:36:9f:2a:63:20 brd ff:ff:ff:ff:ff:ff
> 29: p2p1.91 at p2p1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmnet state UP
>     link/ether a0:36:9f:2a:63:20 brd ff:ff:ff:ff:ff:ff
> 30: vmnet: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP
>     link/ether a0:36:9f:2a:63:20 brd ff:ff:ff:ff:ff:ff
>     inet6 fe80::a236:9fff:fe2a:6320/64 scope link
>        valid_lft forever preferred_lft forever
> 31: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master vmnet state UNKNOWN qlen 500
>     link/ether fe:1a:4a:16:01:58 brd ff:ff:ff:ff:ff:ff
>     inet6 fe80::fc1a:4aff:fe16:158/64 scope link
>        valid_lft forever preferred_lft forever
> 32: vnet1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master vmnet state UNKNOWN qlen 500
>     link/ether fe:1a:4a:16:01:5c brd ff:ff:ff:ff:ff:ff
>     inet6 fe80::fc1a:4aff:fe16:15c/64 scope link
>        valid_lft forever preferred_lft forever
> 
> where vnet1 is the VM interface, and p2p1.91 is the VLAN'd interface for the network. The network the VM nic is on is vmnet, and the physical interface is p2p1
> 
> Configuring an address manually does not help, nor does dropping the firewall on the host.
> I've run the vmnet interface in promiscuous mode to see if I can see anything coming back, but the return traffic does not appear.
> 
> Any ideas as to why the network is not working?
> 
> Thanks for any help.
> 
> -Cam
> 
> 
> _______________________________________________
> Users mailing list
> Users at ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ovirt.org/pipermail/users/attachments/20160915/94658a2b/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 842 bytes
Desc: Message signed with OpenPGP using GPGMail
URL: <http://lists.ovirt.org/pipermail/users/attachments/20160915/94658a2b/attachment-0001.sig>