[CentOS] Interface bonding?

Sat Apr 12 00:51:52 UTC 2008
Les Mikesell <lesmikesell at gmail.com>

John wrote:
>>> Now for what version of the 2900 you have I do not know. But it seems
>>> the info on Ciscos site is kind of misleading in places. There is some
>>> documentation that says it works and some say you have to have the add
>>> on modules. 
>>> Your best bet if your not comfortable with the IOS command line is to
>>> use the Web Interface or the Cisco Works Manager Interface. I say this
>>> because I have really no way of knowing your experiance on this.  I
>>> wouln't do this on a live production switch. 
>> Trunking has to do with carrying multiple tagged vlans on one port - and 
>> the 2900xl with a 12.x IOS should do that in either ISL (cisco) or dot1q 
>>   mode.  But I thought we were grouping ports instead.  You should be 
>> able to do both, but the interfaces in the same port group would have to 
>> have the same trunk encapsulation set.  There is a separate 'vlan 
>> database' command on those switches where you have to add the vlan 
>> numbers that you want a trunk to carry - and it doesn't get saved in the 
>> visible config file.  If you have 'switchport access vlan nnn' on any 
>> interface that number goes in the vlan database automatically but you 
>> just want the trunk ports to pass some other vlans through you have to 
>> add them explicitly.
> '
> Ok, if I am reading your reply right VLAN configs are so to say saved in
> the switch instead of the config file correct? So a config file never
> contains the VLAN info. Just wondering any way to copy or backup the
> VLAN Database? There has to be shouldn't. Been 4 years or more since
> I've touched one. Guess I need to get the newest emulator software Cisco
> has.

Actually it is more complicated that that - the switches have a vtp 
master/slave concept to learn vlans but I've always turned it off 
because the switch with the latest change becomes the master so if 
someone swaps a switch from the lab into production it would probably 
break everything in sight.  As far as backing it up goes, I just keep a 
text file that goes:
vlan database
vlan nnn
vlan nnn
to paste into a new or moved switch.  But I think the new models do 
something different.

   Les Mikesell
    lesmikesell at gmail.com