Question

HP Switch Trunking Causes Loop-back on network

Asked by: TGPC

I have two new HP2824 Procurve Switches, I setup a Trunk on Ports 20 and 21 from the CLI.  When I connect a cable to the rest of the network, a loop back condition happens on the network.  All of the clients start dropping network connections and the entire network goes down.  Does anyone what I have done wrong setting up the Trunk?  Everything is in VLAN0

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Asked On
2009-02-27 at 17:02:23ID24185687
Tags

trunk

,

Ethernet

,

switch

,

procurve

,

loop-back

Topic

Network Switches & Hubs

Participating Experts
6
Points
500
Comments
6

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Answers

 

by: QuoriPosted on 2009-02-27 at 18:21:51ID: 23761378

Provide your configuration please?

 

by: dimantePosted on 2009-02-27 at 18:38:19ID: 23761429

Are the two trunk ports set up just between two switches?

 

by: necati_cehreliPosted on 2009-03-01 at 01:37:13ID: 23767508

What you mean by trunk ? Is this a dot1q trunk or just an access port on the VLAN? Is Spanning Tree enabled on the VLAN you are using ?

 

by: DonbooPosted on 2009-03-01 at 05:47:52ID: 23768123

By default HP switches havnt enabled STP´(Loop detection) so if you havn´t manually enabled it do it.
2nd it sounds like you are connecting 2 access ports to the other switch and not a port trunk with 2 ports in it.

 

by: mickfinleyPosted on 2009-03-02 at 05:17:39ID: 23773721

If both switches are HP use LACP and set to active.  I think STP is enabled by default here, but make sure it is on.

 

by: jburgaardPosted on 2009-03-02 at 07:16:42ID: 23774640

I with donboo ; but please provide config of sw.'s in both ends of link if you still have prob.'s.
Also: first config then connect.

20120131-EE-VQP-002

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