topic Multiple VLANs on a VIF in VMware Solutions Discussions

Multiple VLANs on a VIF

radek_kubka — Thu, 05 Jun 2025 06:52:31 GMT

Hi everybody,

I am trying to configure multiple VLAN interfaces on top of a multimode VIF. In theory all seems to be fine:

fas02> ifconfig -a

[snip]

vif_fas02: flags=0xa2d08863<BROADCAST,RUNNING,MULTICAST,TCPCKSUM,VLAN> mtu 1500

partner vif_fas01 (not in use)

ether 02:a0:98:23:3a:d8 (Enabled virtual interface)

vif_fas02-2: flags=0x2948863<UP,BROADCAST,RUNNING,MULTICAST,TCPCKSUM> mtu 1500

inet 192.168.2.20 netmask-or-prefix 0xffffff00 broadcast 192.168.2.255

partner vif_fas01-2 (not in use)

ether 02:a0:98:23:3a:d8 (Enabled virtual interface)

vif_fas02-70: flags=0x2948863<UP,BROADCAST,RUNNING,MULTICAST,TCPCKSUM> mtu 1500

inet 192.168.70.222 netmask-or-prefix 0xffffff00 broadcast 192.168.70.255

partner vif_fas01-70 (not in use)

ether 02:a0:98:23:3a:d8 (Enabled virtual interface)

vif_fas02-87: flags=0x2948863<UP,BROADCAST,RUNNING,MULTICAST,TCPCKSUM> mtu 1500

inet 192.168.87.221 netmask-or-prefix 0xffffff00 broadcast 192.168.87.255

ether 02:a0:98:23:3a:d8 (Enabled virtual interface)

And on the Cisco 3750 switch side:

interfacePort-channel10

switchport trunk encapsulation dot1q
switchport trunk allowed vlan 2,70,87
switchport mode trunk
end

VLAN 2 interface does work without any problems, yet I cannot ping VLAN 70 and 87 addresses.

As far as I can tell, the only difference is that VLAN 2 has been created first using vlan create command, whilst two others were added later using vlan add command.

Any ideas what the problem could be?

Thanks & regards,
Radek

Multiple VLANs on a VIF

shaunjurr — Wed, 22 Jun 2011 23:50:34 GMT

Hi,

What is the output of 'vif status vif_fas02'? What is the output on the cisco switch of 'sh interface status po10' (iirc)? 3750's have often need to have etherchannel mode forced to "on" instead of desirable.

My memory fails me, but setting vlans on Po interfaces might need to be done on the physical interfaces... You might try to do 'sh trunk' and see which vlans are active and forwarding as well.

All that I can think of at the moment...haven't been a net admin for a few years now. Hope it helps.

Re: Multiple VLANs on a VIF

radek_kubka — Thu, 23 Jun 2011 09:58:45 GMT

Hi,

Thanks for the response!

There is definitely something dodgy going on with the vif at the moment:

fas02> vif status vif_fas02

default: transmit 'IP Load balancing', VIF Type 'multi_mode', fail 'log'

vif_fas02: 1 link, transmit 'IP Load balancing', VIF Type 'multi_mode' fail 'default'

VIF Status Up Addr_set

up:

e0b: state up, since 21Jun2011 16:36:01 (1+18:20:51)

mediatype: auto-1000t-fd-up

flags: enabled

input packets 207275, input bytes 19332659

output packets 24861, output bytes 4813144

up indications 3, broken indications 1

drops (if) 0, drops (link) 0

indication: up at 21Jun2011 16:36:01

consecutive 1920, transitions 8

pending:

e0a: state pending, since 21Jun2011 16:50:16 (1+18:06:36)

mediatype: auto-1000t-fd-up

flags: enabling

input packets 0, input bytes 0

output packets 0, output bytes 0

up indications 0, broken indications 0

drops (if) 0, drops (link) 0

indication: down at 21Jun2011 16:50:16

consecutive 0, transitions 0

As these are the two only ports on the controller, I need to connect via a console cable to reset the ports & the vif.

I am actually going to re-creeate a vif with a vif create command, including all VLANs in question in one go & see what happens.

Regards,

Radek

Re: Multiple VLANs on a VIF

radek_kubka — Thu, 23 Jun 2011 11:56:09 GMT

OK, all solved after:

1) deleting vlans

2) destroying vif

2) creating vif again

3) creating all vlans in one go:

vlan create vif_fas02 2 70 87

I am not 100% sure what helped - the fact that now e0b is no longer in a pending state, or not using vlan add command.

Regards,
Radek

Re: Multiple VLANs on a VIF

radek_kubka — Thu, 23 Jun 2011 14:00:02 GMT

OK, here is the latest:

When we created vif initially, it was on a single physical port only (e0b) & we chose IP-based load balancing. Actually, all addresses on all three VLANs were accessible at that point.Then we added the second physical NIC (e0a) to the vif. All looked fine in the GUI, yet vif status showed that e0a was in a pending state.

So my thinking is: IP-based load balancing means VLAN 2 was pushed via e0b, whilst any additional VLAN was supposed to go via e0a - but the interface wasn't properly up, hence it didn't work.

I just tested it again by vlan delete & vlan add and all works 100% fine.