Setting up ISC and distibuted trunking

[davehedgehog]

I need to setup distributed trunking next week at a site, and I have not done this before. I need to get this done during some scheduled downtime so need to make sure I've got this right in my head :-)

I am planning to link two E3500's together using 2x 1Gb fiber links (ports 47 and 48). The distributed trunks will be for connecting servers to these switches. Each trunk will have one link to each switch. There will be other switches in this stack but they will not setup for DT or ISC so I assume they are not relevant.

For the ISC setup I think I need these commands...

ProCurve Switch 1(config)# trunk 47-48 trk1 lacp
ProCurve Switch 1(config)# switch-interconnect trk1
ProCurve Switch 2(config)# trunk 47-48 trk1 lacp
ProCurve Switch 2(config)# switch-interconnect trk1

I have read somewhere that I need to setup a peer-keepalive link on a separate VLAN. I assume that I create a new VLAN on each switch (let's say VLAN10) and give the VLAN interfaces IP addresses for example 10.0.0.1 and 10.0.0.2

Then I think I just use these commands to enable the keepalive (not sure if I have to do it on both switches but I assume so)...

ProCurve Switch 1(config)# distributed-trunking peer-keepalive destination 10.0.0.2 source 10.0.0.1 vlan 10 interval 1000 timeout 5 hold-timer 6 udp-port 6400

ProCurve Switch 2(config)# distributed-trunking peer-keepalive destination 10.0.0.1 source 10.0.0.2 vlan 10 interval 1000 timeout 5 hold-timer 6 udp-port 6400

Then lastly to setup the distributed trunk (trk2) to connect a server to port 7 on each switch, I would do the following...

ProCurve Switch 1(config)# trunk 7 trk2 dt-lacp

ProCurve Switch 2(config)# trunk 7 trk2 dt-lacp

Please can someone confirm the above is correct. Not got the hardware to test it here so need some reassurance :-)

[ISoliman · Accepted solution]

For the keepalive VLAN you need to have a seperate physical link and untag that port from the link to this vlan in both switches.

And for the trk between the 2 switches it should be configured like this:

ProCurve Switch 1(config)# trunk trk7 47-48 dt-lacp

ProCurve Switch 2(config)# trunk trk7 47-48 dt-lacp

and make sure to confiogure that after configuring the keep-alive vlan, check the below technical paperfrom HP that explains everything in detailed step by step, make sure to use the latest firmware K.15.06.0008 in both switches.

make sure that the DT will be from 1 server to the 2 switches not from 2 different servers to the 2 switches.

http://h20195.www2.hp.com/v2/GetDocument.aspx?docname=4AA3-4841ENW&doctype=white%20paper&doclang=EN_US&searchquery=&cc=uk&lc=en

[davehedgehog]

Hi thanks for your advice, all working now :-)

[Matt Kunard]

The ISC trunk link between the two switches is a regular LACP trunk, you do not use the "dt lacp" designation there, only on the downlink ports on the two DT switches leading to the device that you're creating the link aggregation group to. 

[davehedgehog]

Yeah I did deviate a little from the example above. I ended up with this config...

The firmware version didn't allow the keepalive either so that got left out too :-)

switch-interconnect Trk1

trunk 47-48 Trk1 LACP
trunk 45-46 Trk2 LACP
trunk 23-24 Trk3 dt-lacp
trunk 25 Trk4 dt-lacp

[ISoliman]

OH right I got confused between the links to the servers and between the switches sorry for that :D

Just make sure you are using the latest firmware available as they have fixed LOT of issues in the DT :)

[darrenlynn]

Hi All,

this configuration has been driving me insane.... (Im new to HP)

I have 2 8212's runnnig K.15.8.

I have 2 x 10GB links between the Switches C21, D21 on both switch set up as Trk1 and LACP

I enable ISC for Trk1 and iteverything looks ok

When i enable dt-LACP on the trunk (via the menu is the only way ive found) the LACP goes into blocked state.

I also have a dedicated peer link on port D20 on both switches, untagged for VLAN 30. IP address 10.202.7.33 and 10.202.7.34 on switch 1 and 2 respectively. I can ping each side via this link.

It doesnt matter is i have Spanning Tree enabled or disabled.

Ive read the white paper posted in this link numerous times and i just cant make the configuration work when I enable DT-LACP.

Is anyone able to assist?

Cheers

Darren

[ISoliman]

In both Cores configure:

trunk C21,D21 Trk1 lacp
switch-interconnect Trk1

distributed-trunking peer-keepalive vlan 30
distributed-trunking peer-keepalive destination 10.202.7.33 (IP of other core switch)

Ports that are connecting to the servers or other switches should be configured the same in both cores with the same trunk name/number

trunk x trkx dt-lacp

make sure VLAN 30 is only having port D20 in both Cores, use the comman "show vlan 30"

Also I would recommend configure the ISC trunk using static trunk instead of LACP, also from the end device that has its ports connected to the 2 cores make sure you are configuring the 2 ports as LACP trunk or team.

[darrenlynn]

Hi,

Thanks for the assistance.

once question, why would you use "Trunk" and not "LACP" for the ISC connection.

I understand LACP to be bundling the 2 x 10G connections so to enable resilliancy should one of the modules / ports fail (similar to Cisco Etherchannel)

Im interested to understand your reasoning behind that decision.

Cheers

Darren

[ISoliman]

"TRUNK" & LACP both are link aggregation but TRUNK is more stable since it is static it doesn't need any negotiation not like LACP which negotiate the link between the 2 sides, I'm always using TRUNK for the link between the 2 Cores.

you will get the same result regarding bundling the 2 X 10G ports using TRUNK for resiliency.