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sleeycat_111636's avatar
sleeycat_111636
Icon for Nimbostratus rankNimbostratus
Oct 20, 2009

trunk or not

We just received two pairs of 6900s and I have basic setup question would like to get help.

 

 

There will be one internal vlan, four 1G ports untagged assigned to

 

internal vlan, should we trunk the four ports and add the trunk to the

 

vlan or just add the four interface directly to the vlan, won't we also get 4G throughput by adding four interfaces directly to the vlan?

 

 

Also,we plan to have another four ports trunked and assigned as tagged interfaces to three external vlans.

 

 

Since this is basic setup question(difficult to change once the system is configure one way the other).

 

 

I appreciate all your help!
config
design
  • DeVon_Jarvis's avatar
    DeVon_Jarvis
    Icon for Altostratus rankAltostratus
    Oct 21, 2009
    I would trunk the interfaces and use LACP is possible. Not sure what would happen if you assign 4 interfaces to the same vlan, but it definitely won't be coordinated with the switch!

     

     

    We use this config and it works very well. As well as providing higher throughput, you also get redundancy for link failure.

     

     

    DeVon
  • sleeycat_111636's avatar
    sleeycat_111636
    Icon for Nimbostratus rankNimbostratus
    Oct 21, 2009
    Thanks for replying. I search the forum but couldn't find example on on trunk setup for example, Cisco fast etherChannel and F5

     

     

    This article mentions not to use auto-negotiate which is the default,

     

    also says no support for dynamic aggregation protocols such as LACP/PAGP on BIG-IP, I guess it's availalbe on LTM now, right?

     

    https://support.f5.com/kb/en-us/solutions/public/3000/000/sol3018.html

     

     

    I have another default Gateway question, there will be three external vlans host three different networks, each has default gateway configured on the Cisco router, which is the F5 trunk connected to,

     

    should we setup three default gateways, one for each network?

     

     

    Thanks!
  • Anthony_5437's avatar
    Anthony_5437
    Icon for Nimbostratus rankNimbostratus
    Nov 16, 2009
    Trunk & Tag - YES; everywhere you can as long as it fits your security model.

     

    LACP/PAgP - YES, use LACP (you can't use PAgP since it is Cisco proprietary).

     

    Speed/Duplex - Autonegotiate; as a rule I always autonegotiate if it is 1000mb.

     

     

    As for the config on your Cisco switch, it should look something like this with most of the config taking place on the port-channel and not the individual interfaces:

     

     

    interface Port-channel1

     

    description BigIP1

     

    switchport

     

    switchport trunk encapsulation dot1q

     

    switchport trunk native vlan 999

     

    switchport mode trunk

     

    switchport nonegotiate