Cisco 3660 dot1q support

[craigeb78]

Saw a thread awhile back about Cisco 2500's and dot1q support on ethernet and fast ethernet sub interfaces so if figure I'd post my problem.

I have a Cisco 3660 1 builtin FE and 2 Ethernet cards. All of the interfaces will allow me to create a subinterface but none will let me set encapsulation to do trunking:

myrouter#config t
Enter configuration commands, one per line. End with CNTL/Z.
myrouter(config)#int ethernet2/0.1
myrouter(config-subif)#enca?
% Unrecognized command
myrouter(config-subif)#?
Interface configuration commands:
arp Set arp type (arpa, probe, snap) or timeout
backup Modify backup parameters
bandwidth Set bandwidth informational parameter
bridge-group Transparent bridging interface parameters
carrier-delay Specify delay for interface transitions
cdp CDP interface subcommands
default Set a command to its defaults
delay Specify interface throughput delay
description Interface specific description
exit Exit from interface configuration mode
ip Interface Internet Protocol config commands
llc2 LLC2 Interface Subcommands
mls mls router sub/interface commands
mtu Set the interface Maximum Transmission Unit (MTU)
netbios Use a defined NETBIOS access list or enable name-caching
no Negate a command or set its defaults
ntp Configure NTP
rate-limit Rate Limit
service-policy Configure QoS Service Policy
shutdown Shutdown the selected interface
snapshot Configure snapshot support on the interface
standby Hot standby interface subcommands
timeout Define timeout values for this interface
traffic-shape Enable Traffic Shaping on an Interface or Sub-Interface

Heres my software version on this router:

IOS (tm) 3600 Software (C3660-I-M), Version 12.0(7)T, RELEASE SOFTWARE (fc2)
This is my old system.

I also have a new system with the EXACT same symptoms running:

IOS (tm) 3600 Software (C3660-I-M), Version 12.3(1a), RELEASE SOFTWARE (fc1)

I thought this was suppose to be supported by default.

Anyone know what gives?

 

[spidey07]

you set the encapsulation on the interface, not the sub interface

int e2/0
encap 802.1q

although there are some limitations on 10 Base-T interfaces and trunking. some support it, some don't

 

[polm]

Originally posted by: spidey07
you set the encapsulation on the interface, not the sub interface

int e2/0
encap 802.1q

although there are some limitations on 10 Base-T interfaces and trunking. some support it, some don't

hmm..that 2611 I was talking about yesterday allows me to set the encap only on the sub-if. But it's also 10mbit, so not so sure it really supports the dot1q encapsulation.

 

[spidey07]

Originally posted by: polm

Originally posted by: spidey07
you set the encapsulation on the interface, not the sub interface

int e2/0
encap 802.1q

although there are some limitations on 10 Base-T interfaces and trunking. some support it, some don't

hmm..that 2611 I was talking about yesterday allows me to set the encap only on the sub-if. But it's also 10mbit, so not so sure it really supports the dot1q encapsulation.

check the features matrix for your version of IOS and the model number, that will tell you.

dang Polm. I'm gonna have to start charging you for all the training.


http://www.cisco.com/en/US/products/sw/...cts_feature_guide09186a008008742b.html

Although I do remember that trunking wasn't supported on 10 meg interfaces with IOS 12.0, seems it has been resolved since then though.

 

[randal]

In an earlier thread I was notified that interfaces that do not support dot1q (any eth + IOS < 12.2(?)) will still have sub-interfaces available -- for use with IPX/SPX only.

 

[polm]

Originally posted by: spidey07

Originally posted by: polm

Originally posted by: spidey07
you set the encapsulation on the interface, not the sub interface

int e2/0
encap 802.1q

although there are some limitations on 10 Base-T interfaces and trunking. some support it, some don't

hmm..that 2611 I was talking about yesterday allows me to set the encap only on the sub-if. But it's also 10mbit, so not so sure it really supports the dot1q encapsulation.

check the features matrix for your version of IOS and the model number, that will tell you.

dang Polm. I'm gonna have to start charging you for all the training.

Hey, it's not my fault IOS is screwed up. Your telling me the dot1q encap on a 3600 is set on the interface and for a 2600 would be set on the sub-interface?


According to this I am not supposed to be able to support withouth IOS 12.2(5), but I'm seeing the command options with 12.1(20), I'm guessing they wont work.

Oh well, for now I'll just split the two vlan subnets on E0/0 and E0/1, and save the trunking when I can get upgraded hardware.

I don't think my company has introduced any 12.2 stuff onto the production network, therefore upgrading the image just isn't an option for this device.

 

[craigeb78]

And on my 3660, I dont get encapsulation options on ANY ethernet interface. Sub or not. This goes for my 12.0(7)T and 12.3(1a).
Drives me nuts that I don't know why Edit: Think I figured this out. I have the standard IP feature set loaded. From the way it looks, I may need IP plus. Does this sound right?

On another note, in my sh ver, I have a line that says Bridging software. This is on both of my routers, is this standard or did the admin before me put something on these?

-Craig

 

[bgroff]

Good god folks, this is an easy one.

You're running Ip software. The encapsulation is only available on Plus or Service Provider images. The I in C3660-I-M means IP Only. You need to Have C3660-IS-M. The IS means IP Plus. And the encapsulation statement goes on the sub interface. You create the new subinterface and then associate it with a tagged vlan (though vlan 1 likes to be untagged). The physical interface is also the untagged interface if no other subinterface has the untagged designation.

Have fun!