Etherchannel problem for 6500 VSS

[Sanjay Shaw]

Hello Team,

Could anyone suggest if I use lots of etherchannel configuration running between my access(4500) and DS(6500)  may create any etherchannnel issue. As in my enviroment I am experiecing my access switch bundled interfaces getting down and we have to manually replug the cable to up the etherchannel bundle.

Is there any oversubscription happenning in my 6500 chasis which causing the bundle to get in down state. Logs at both the end only suggest for the interface flaps.

Note: 6500 is in VSS.

6506-E#  sh etherchannel summary

Flags:  D - down        P - bundled in port-channel

        I - stand-alone s - suspended

        H - Hot-standby (LACP only)

        R - Layer3      S - Layer2

        U - in use      N - not in use, no aggregation

        f - failed to allocate aggregator

        M - not in use, no aggregation due to minimum links not met

        m - not in use, port not aggregated due to minimum links not met

        u - unsuitable for bundling

        d - default port

        w - waiting to be aggregated

Number of channel-groups in use: 27

Number of aggregators:           27

Group  Port-channel  Protocol    Ports

------+-------------+-----------+-----------------------------------------------

1      Po1(RU)          -        Te1/5/4(P)     Te1/5/5(P)

2      Po2(RU)          -        Te2/5/4(P)     Te2/5/5(P)

3      Po3(SU)          -        Gi1/1/3(P)     Gi2/1/3(P)

10     Po10(SU)         -        Gi1/1/5(P)     Gi2/1/5(P)

11     Po11(SU)         -        Gi1/1/6(P)     Gi2/1/6(P)

14     Po14(SD)         -

17     Po17(SU)         -        Gi2/1/4(D)     Gi2/2/14(P)

19     Po19(SU)         -        Gi1/1/14(P)    Gi2/1/14(P)

20     Po20(SU)         -        Gi1/1/15(P)    Gi2/1/15(P)

21     Po21(SU)         -        Gi1/1/16(P)    Gi2/1/16(P)

22     Po22(SU)         -        Gi1/1/17(P)    Gi2/1/17(P)

23     Po23(SU)         -        Gi1/1/18(P)    Gi2/1/18(P)

24     Po24(SU)         -        Gi1/1/19(P)    Gi2/1/19(P)

25     Po25(SU)         -        Gi1/1/20(P)    Gi2/1/20(P)

26     Po26(SU)         -        Gi1/1/21(P)    Gi2/1/21(P)

27     Po27(SU)         -        Gi1/1/22(P)    Gi2/1/22(P)

28     Po28(SU)         -        Gi1/1/23(P)    Gi2/1/23(P)

29     Po29(SU)         -        Gi1/1/24(P)    Gi2/1/24(P)

30     Po30(SU)         -        Gi1/2/1(P)     Gi2/2/1(P)

31     Po31(SU)         -        Gi1/2/2(P)     Gi2/2/2(P)

32     Po32(SU)         -        Gi1/2/3(P)     Gi2/2/3(P)

33     Po33(SU)         -        Gi1/2/4(P)     Gi2/2/4(P)

34     Po34(SU)         -        Gi1/2/5(P)     Gi2/2/5(P)

35     Po35(SU)         -        Gi1/2/6(P)     Gi2/2/6(P)

36     Po36(SU)         -        Gi1/2/7(P)     Gi2/2/7(P)

37     Po37(SU)         -        Gi1/2/8(P)     Gi2/2/8(P)

38     Po38(SU)         -        Gi1/2/9(P)     Gi2/2/9(P)

[Wilson Bonilla · Accepted solution]

Hello Sanjay

Is there any oversubscription happenning in my 6500 chasis which causing the bundle to get in down state. Logs at both the end only suggest for the interface flaps.

Oversubscription may happen at linecard and ASIC level, But I don't  think oversubscription has anything to do with the problem your switch is experiencing.

In regards to oversubscription here is an example

WS-X6724-SFP

Port ranges per port group: 1-12, 13-24

Oversubscription rate 1:12 (One ASIC every 12 ports)

Look at this link for further information about oversubscription in each module.

http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/hardware/Module_Installation/Mod_Install_Guide/02ethern.html#wp1040314

The VSS supports up to 512 Etherchannels combined the total amout of regular etherchannels and MEC.