Re: STP question// LACP

Hi Ramesh,

Please take caution if this is a live production network!!

That said I just tested this between two Catalyst 3550's
running 12.2(44)SE6 and I was able to add UDLD commands to a single
interface in the bundle without issue. Here is my configuration before
adding UDLD:

SW1

interface range FastEthernet0/41 - 48
 description *-* LACP to SW2 *-*
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 8 mode active

SW2

interface range FastEthernet0/41 - 48
 description *-* LACP to SW1 *-*
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 8 mode active

Verification shows EtherChannel is good

SW1#show etherchannel summary | beg Group
Group Port-channel Protocol Ports
------+-------------+-----------+-----------------------------------------------
8 Po8(SU) LACP Fa0/41(P) Fa0/42(P) Fa0/43(P)
                                 Fa0/44(P) Fa0/45(P) Fa0/46(P)
                                 Fa0/47(P) Fa0/48(P)

Now to add UDLD commands only to Fa0/48 on both sides

SW1

interface FastEthernet0/48
 udld port aggressive

SW2

interface FastEthernet0/48
 udld port aggressive

Nothing dropped and thatEtherChannel is still up

SW1#show etherchannel summary | begin Po8
8 Po8(SU) LACP Fa0/41(P) Fa0/42(P) Fa0/43(P)
                                 Fa0/44(P) Fa0/45(P) Fa0/46(P)
                                 Fa0/47(P) Fa0/48(P

And we also have UDLD neighbors as well

SW1#show udld neighbors
Port Device Name Device ID Port ID Neighbor State
---- ----------- --------- ------- --------------
Fa0/48 CHK0645V0MJ 1 Fa0/48 Bidirectional

Again take caution in production network but it worked fine in the lab :)

HTH

On Mon, Feb 4, 2013 at 7:59 PM, ramesh Kumar <rameshkumar123321_at_yahoo.com>wrote:

> Thanks Steve,
>
> For troubleshooting purposes, i want to enable it only on the suspended
> port. Is it possible to enable it on only a single port-channel member or
> is it mandatory to enable on the entire port-channel members? We cant
> bounce the link as it is production.
>
> Ramesh
>
> ------------------------------
> *From:* Steve Di Bias <sdibias_at_gmail.com>
> *To:* marc abel <marcabel_at_gmail.com>
> *Cc:* ramesh Kumar <rameshkumar123321_at_yahoo.com>; Cisco certification <
> ccielab_at_groupstudy.com>
> *Sent:* Tuesday, February 5, 2013 8:53 AM
>
> *Subject:* Re: STP question// LACP
>
> Configure it on all of the physical interfaces and not on the port-channel
> itself.
>
> Int range x/x
> udld port <aggressive>
>
> Just make sure you do this on both sides and you can view with 'show udld
> neighbors'
>
> HTH
>
>
> On Monday, February 4, 2013, marc abel wrote:
>
> > Have you bounced all ends of all the links or is this a production link?
> > On Feb 4, 2013 9:11 PM, "ramesh Kumar" <rameshkumar123321_at_yahoo.com<javascript:_e({},
> 'cvml', 'rameshkumar123321_at_yahoo.com');>>
>
> > wrote:
> >
> >> Hi Steve,
> >>
> >> The configs are identical both sides.
> >>
> >> I am suspecting
> >> unidirectional link issue. when i do show lacp counters port-channel
> <ID>
> >> it
> >> shows LACP PDU being sent but not received at both ends
> >> I am planning to
> >> enable UDLD and see. But I am wondering can we enable UDLD on a single
> >> port-channel member or it has be enabled on the entire port-channel
> >> interface?
> >> can you please assist?
> >>
> >> Ramesh
> >>
> >>
> >> ________________________________
> >> From: Steve
> >> Di Bias <sdibias_at_gmail.com <javascript:_e({}, 'cvml',
> >> 'sdibias_at_gmail.com');>>
> >> To: ramesh Kumar <rameshkumar123321_at_yahoo.com <javascript:_e({},
> 'cvml',
> >> 'rameshkumar123321_at_yahoo.com');>>
> >> Cc: "ccielab_at_groupstudy.com <javascript:_e({}, 'cvml',
> >> 'ccielab_at_groupstudy.com');>" <ccielab_at_groupstudy.com <javascript:_e({},
> >> 'cvml', 'ccielab_at_groupstudy.com');>>
>
> >> Sent: Saturday,
> >> February 2, 2013 11:15 PM
> >> Subject: Re: STP question// LACP
> >>
> >> No TCN since STP
> >> is running at the PortChannel level. It will however send
> >> a trap and will how
> >> up in your local log buffer:
> >>
> >> If a segment within an EtherChannel fails,
> >> traffic previously carried over
> >> the failed link switches to the remaining
> >> segments within the EtherChannel.
> >> When a failure occurs, the EtherChannel
> >> feature sends a trap that
> >> identifies the switch, the EtherChannel, and the
> >> failed link.
> >>
> >> Regarding LACP an suspended link. Could you please provide
> >> interface
> >> configs from all ports on both sides? Are they all identical?
> >>
> >>
> >>
> >>
> >> On
> >> Sat, Feb 2, 2013 at 5:08 AM, ramesh Kumar <rameshkumar123321_at_yahoo.com<javascript:_e({},
> 'cvml', 'rameshkumar123321_at_yahoo.com');>
>
> >> >wrote:
> >> > Hello,
> >> >
> >> > I have a port-channel of 8 links. one of them went to suspended
> >> state.
> >> > i took that link out of PO and the came back up as normal but adding
> >> it
> >> > back
> >> > to the PO it goes to the suspend state. the config at both end are
> >> the
> >> > same.
> >> > they are doing LACP and mode is set to be active at both ends.
> >> What else we
> >> > can try here? any clue?
> >> >
> >> > Also i would like to know if any
> >> STP tcn is generated
> >> > when a port-channel link moves to suspend state or not.
> >> >
> >> > please advice.
> >> > Ramesh
> >> >
> >> >
> >> > Blogs and organic groups at
> >> http://www.ccie.net
> >> >
> >> >
> >> _______________________________________________________________________
> >> >
> >> Subscription information may be found at:
> >> >
> >> http://www.groupstudy.com/list/CCIELab.html
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >>
> >>
> >> --
> >> Thank you,
> >> Steve Di Bias
> >> CCIE #32840
> >>
> >>
> >> Blogs and organic groups at http://www.ccie.net
> >> _______________________________________________________________________
> >> Subscription information may be found at:
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> >>
> >>
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> >>
> >> _______________________________________________________________________
> >> Subscription information may be found at:
> >> http://www.groupstudy.com/list/CCIELab.html
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
>
> --
> Steve Di Bias- CCIE #32840
> Sent from Gmail Mobile
>
>
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>
> _______________________________________________________________________
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-- 
Thanks,
Steve Di Bias- CCIE #32840
Blogs and organic groups at http://www.ccie.net