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port 7 is Blocked by LACP

Gabriel Balogh
Occasional Visitor

port 7 is Blocked by LACP

Dear All!

Our customer experiences a problem with ProCurve Switch 2650. PCs connected to siwtch are losing connection.
Siwtch is logging e.g.

I 01/15/90 20:02:47 ports: port 7 is now off-line
I 01/15/90 20:02:49 ports: port 7 is Blocked by LACP
I 01/15/90 20:02:52 ports: port 7 is now on-line
I 01/15/90 20:04:28 ports: port 7 is now off-line
I 01/15/90 20:04:30 ports: port 7 is Blocked by LACP
I 01/15/90 20:04:33 ports: port 7 is now on-line

however :

HP ProCurve Switch 2650# show lacp
---- ------- ------- ------- ------- -------
1 Passive 1 Up No Success
2 Passive 2 Up No Success
3 Passive 3 Up No Success
4 Passive 4 Up No Success
5 Passive 5 Up No Success
6 Passive 6 Up No Success
7 Passive 7 Up No Success


HP ProCurve Switch 2650# write term
; J4899A Configuration Editor; Created on release #H.07.02
hostname "HP ProCurve Switch 2650"
cdp run
ip default-gateway
ip routing
no timesync
snmp-server community "public" Unrestricted
snmp-server host "public" Not-INFO
vlan 1
untagged 1-50
ip address
fault-finder bad-driver sensitivity high
fault-finder bad-transceiver sensitivity high
fault-finder bad-cable sensitivity high
fault-finder too-long-cable sensitivity high
fault-finder over-bandwidth sensitivity high
fault-finder broadcast-storm sensitivity high
fault-finder loss-of-link sensitivity high

HP J4899A ProCurve Switch 2650
H.07.02, ROM H.07.01

1) It seems to be, that ports are in "PASSIVE" LACP mode, than why LACP is blocking ports? Is there a configuration error ?
2) Because of low sw version I suggested upgrade to H.07.31
3) BUT, I could not find this problem in solved Problem Reports on external web site.
4) Where I can find complete problem reports for this product and in which release was solved ?



Arimo Laine_2
Valued Contributor

Re: port 7 is Blocked by LACP


The questions first:

1. If you look at the log you will notice that what happens is in sequence:
- port goes offline
- LACP blocks port
- port comes online
Basic LACP functionality is that whenever a link comes online, passive LACP will kick in and block the port until it knows if it has an active partner. If it does, it will create a trunk, if not, it will release the port. This most likely is a configuration issue, but not in LACP.

2. Shortly, yes. Always use the latest FW, there's usually good reasons for new FW release.

3 & 4. There's neither software fix nor a problem report as this is not a problem or error, but as I said basic LACP functionality.

Most likely the problem is Duplex Mismatch on the link, see http://e2epi.internet2.edu/CaseStudies/SC02/DuplexMismatch.html.

To get rid of this, first make sure that both ends of the link are configured to the same speed-duplex setting, i.e. Auto to Auto or FDx to FDx, but NOT Auto to FDx. It might be also good idea to update the NIC driver, if this is a PC.

Next, disable LACP completely if you do not use it in trunking (= link aggregation). You do not really lose anything, as there are still 2 aggregation methods left, HP port trunking and FEC, if you want to use it. This is done in switch command line with commands

con t
int all
no lacp
write mem

This does not require a switch reset.

This should solve the problem.