Wired Intelligent Edge

Disclaimer: I am new to Aruba and not a full-time network person.

I set my four new 2930F's up on the workbench and configured a single four-member VSF. Each additional unit was added to the VSF in turn and labeled #2, #3, and #4. These are replacing obsolete switches in an operating LAN.

Everything was mounted in the rack and reconnected on Saturday. Each unit was powered up in member order and all the LEDs looked good but our test laptop couldn't get to the default gateway or a couple of the servers. A patch cable between #2 and #3 made that problem go away and on Monday there have been no calls from anybody with connectivity problems.

Plugged into #1 (the commander) I see a VSF with three active members and one missing member. The unit labeled #4 is #3 in the VSF and the one labeled #3 is missing. Plugging into #3 shows it is commander of another VSF with three missing members.

The stacking cables appear to be correct (at least for Dell switches).

1 top = 4 bottom

1 bottom = 2 top

2 bottom = 3 top

3 bottom = 4 top

Is this correct?

To turn my two VSF's into one can I just reboot #3 (the one in its own VSF)? Since this is all in production I can't just do it now and see what happens. Do I need to factory-default it?

Greetings!

You should be able to merge your VSF stack into its original configuration by making sure that the cables between members are connected to the correct VSF link ports — you can verify the correct ports by using the following command on the Commander (the exact output will be different):

switch(config)# show vsf link detail 

 VSF Member: 1     Link: 1

 Port     State                                                             
 -------- ------------
 1/49     Up: Connected to port 2/27                                        
 1/50     Up: Connected to port 2/28                                        


 VSF Member: 1     Link: 2

 Port     State                                                             
 -------- ------------
 1/51     Up: Connected to port 3/27                                        


 VSF Member: 2     Link: 1

 Port     State                                                             
 -------- ------------
 2/27     Up: Connected to port 1/49                                        
 2/28     Up: Connected to port 1/50                                        


 VSF Member: 2     Link: 2

 Port     State                                                             
 -------- ------------
 2/25     Up: Connected to port 3/25                                        
 2/26     Up: Connected to port 3/26                                        


 VSF Member: 3     Link: 1

 Port     State                                                             
 -------- ------------
 3/25     Up: Connected to port 2/25                                        
 3/26     Up: Connected to port 2/26                                        


 VSF Member: 3     Link: 2

 Port     State                                                             
 -------- ------------
 3/27     Up: Connected to port 1/51                                        

Look for any port that has a Down state, and double-check the physical connections on each member and move cables as appropriate.

Once the VSF links are connected properly, a VSF merge will occur, causing members in one or both fragments to reboot (ideally, only the single isolated member in this instance), then rejoin the fabric as a VSF member.

Be sure to refer to the best practices guide attached to this post for additional suggestions and troubleshooting methods. 

HI Matthew,

Thanks very much for your quick response. Running the show vsf link detail also allowed me to see which member was actually which.

I got a "Error: Unknown"  on 2/49, which is plugged into the missing 4/50. 4/49 and 4/50 show as "Provisioned". Member 3's Link 2 (which is plugged into 4/49) doesn't appear at all.

Running show vsf link reports that 2/2, 3/2, 4/1, and 4/2 are down. Regarding the arrangement of stacking cables, I followed the Dell PowerConnect arrangement which was first port on top unit to second port on bottom unit; second port on top unit to first port on second unit  as shown below. Is this all wrong for 2930F and the source of my problems or does it not really matter ?

As VSF is a 'front plane' stacking protocol utilizing regular switch ports, you can specify which ports are used for VSF links in the switch configuration. As long as all ports are the same speed, it does not matter which physical ports are actually configured.

Could you post the full output of 'show vsf link detail' so we can figure out which links are which, and how the 3-member fragment itself is connected?

Here is the output:

Aruba-VSF-2930F(config)# show vsf link detail

VSF Member: 1 Link: 1

Port State
-------- ------------
1/49 Up: Connected to port 2/50

VSF Member: 1 Link: 2

Port State
-------- ------------
1/50 Up: Connected to port 3/49

VSF Member: 2 Link: 1

Port State
-------- ------------
2/49 Error: Unknown
2/50 Up: Connected to port 1/49

VSF Member: 3 Link: 1

Port State
-------- ------------
3/49 Up: Connected to port 1/50

VSF Member: 4 Link: 1

Port State
-------- ------------
4/50 Provisioned

VSF Member: 4 Link: 2

Port State
-------- ------------
4/49 Provisioned

Are you trying to connect these four switches in a ring, or a chain? The former is recommended for reliability, but may not be practical if you're also using the SFP(+) ports as uplinks for the fabric.

In a chain topology, if members are connected in order:

• Member 1 is connected to member 2;
• Member 2 is connected to members 1 and 3;
• Member 3 is connected to members 2 and 4;
• Member 4 is connected to member 3

To complete the ring topology, add a link between members 1 and 4.

Importantly, connections between different members must be assigned to different VSF links — any ports connected to the same neighbor must be part of the same VSF link.

Based on the output you posted, it appears that member 1 has connections to both members 2 and 3; members 2 and 3 have no second VSF link; and member 4 appears entirely isolated. Here are my recommendations (this will require taking the stack out of service for reconfiguration and recabling):

First: remove port 2/49 from VSF link 1 on member 2, and add it to VSF link 2:

switch(config)# no vsf member 2 link 1 2/49
switch(config)# vsf member 2 link 2 2/49

Second: add port 3/50 to VSF link 2 on member 3:

switch(config)# vsf member 3 link 2 3/50

Third: Ensure cables are connected to ports as follows:

• 1/49 <==> 2/50
• 2/49 <==> 3/50
• 3/49 <==> 4/50
• 4/49 <==> 1/50

Once everything is connected properly and the VSF merge is complete, the stack should operate as expected. 

Thanks very much for this. Last night trying to merge the stack I ended up splitting into three fragments, and decided to just default everything and start over. It is now set up as a  ring:

vsf member 1 link 1 1/49
vsf member 1 link 2 1/50
vsf member 2 link 1 2/49
vsf member 2 link 2 2/50
vsf member 3 link 1 3/49
vsf member 3 link 2 3/50
vsf member 4 link 1 4/49
vsf member 4 link 2 4/50

I should leave well enough alone as it's finally working but I still have the 51/52 ports. Can I just get some more cables and reenter the above with 51's and 52's for even better performance or will that make me regret my life choices like I was doing last night after making everything much worse and going way over my maintenance window?

As long as the ports you add to each VSF link are connected to the same members as the existing ports on the same link, there should be no issues — where problems tend to pop up is when VSF link ports are moved or disconnected, rather than adding new ones.

Great. Thanks very much for your help!