05-30-2010 01:18 AM - edited 03-06-2019 11:20 AM
Hey everybody,
I just added a new switch to our stack in our server room. The stack had 5 members, and the 6th was a member from another stack in another server room.
Here's what I did:
Everything booted properly and the stack reformed with the new 6th Switch, however the connection between Switches 4 and 5 is now in a "down" state, even after connecting the cable again from 5 to 6. Note: I did not originally do anything to the cable between Switches 4 and 5.
Stack Port Status Neighbors
Switch# Port 1 Port 2 Port 1 Port 2
--------------------------------------------------------
1 Ok Ok 2 6
2 Ok Ok 1 3
3 Ok Ok 4 2
4 Ok Down 3 None
5 Down Ok None 6
6 Ok Ok 5 1
Did this happen because I booted the new switch with only one port connected to the stack?
What will happen if I reload switch 6? Won't switches 4 and 5 lose connectivity to one another because they don't have a link between themselves?
I can't really reload this entire stack because it's switching for our server room and those servers need to be up 24/7.
05-30-2010 11:39 PM
Hey everybody,
I just added a new switch to our stack in our server room. The stack had 5 members, and the 6th was a member from another stack in another server room.
Here's what I did:
Everything booted properly and the stack reformed with the new 6th Switch, however the connection between Switches 4 and 5 is now in a "down" state, even after connecting the cable again from 5 to 6. Note: I did not originally do anything to the cable between Switches 4 and 5.
Stack Port Status Neighbors
Switch# Port 1 Port 2 Port 1 Port 2
--------------------------------------------------------
1 Ok Ok 2 6
2 Ok Ok 1 3
3 Ok Ok 4 2
4 Ok Down 3 None
5 Down Ok None 6
6 Ok Ok 5 1
Did this happen because I booted the new switch with only one port connected to the stack?
What will happen if I reload switch 6? Won't switches 4 and 5 lose connectivity to one another because they don't have a link between themselves?
Hi,
Check out the below link for adding and removing a switch from the stack.
Hope to help !!
Ganesh.H
05-31-2010 12:35 AM
Hi Ganeshh,
that's the guide I used to add the 6th switch to the stack. I didn't touch the connection between Switches 4 and 5. Compatibility-wise, everything seems OK: All 5 Switches have the same IOS image and they stack just fine:
H/W Current
Switch# Role Mac Address Priority Version State
----------------------------------------------------------
*1 Master 0012.d93b.5380 15 0 Ready
2 Member 0014.6a75.0580 14 0 Ready
3 Member 0015.f9bb.d980 13 0 Ready
4 Member 0015.f97b.7e00 12 0 Ready
5 Member 0018.1900.df80 11 0 Ready
6 Member 0017.e0de.1100 10 0 Ready
The problem is that the link between 4 and 5 went down during the process. Because Switch 5's only connection to the stack is through Switch 6, I cannot reasonably "undo" what I did, because doing so would mean all the servers plugged in to Switch 5 would lose connectivity, and we can't have that.
I've checked the cable between Switches 4 and 5, connected it and reconnected it a dozen times, making sure the screws were finger tight and uniform all around, with no wiggle on the connector. I've even exchanged the cable with a cable I know to work, but the link is still down.
I've thought about reloading Switch 6, but I can only assume that doing so would also cause Switch 5 to lose connectivity to the stack and cause lots of problems.
Edit: To be more accurate, I looked through the logs and found that the Stack Port connection between switches 4 and 5 went down shortly after Switch 6 came up and joined the stack. Like I said before, I waited to complete the ring until after Switch 6 had joined. Until that point, Switch 6 was connected to Switch 1. It wasnt until I connected Switch 6 to Switch 5 that the link between Switch 5 and Switch 4 went down.
Logs:
May 29 12:54:42: %STACKMGR-5-SWITCH_READY: Switch 6 is READY (RT-BACKBONE-6)
May 29 12:56:49: %STACKMGR-4-STACK_LINK_CHANGE: Stack Port 2 Switch 4 has changed to state DOWN
May 29 12:56:50: %STACKMGR-4-STACK_LINK_CHANGE: Stack Port 1 Switch 6 has changed to state UP
May 29 12:56:50: %STACKMGR-4-STACK_LINK_CHANGE: Stack Port 1 Switch 5 has changed to state DOWN
May 29 12:56:50: %STACKMGR-4-STACK_LINK_CHANGE: Stack Port 2 Switch 5 has changed to state UP
As you can see, Switch 6 joined the stack without problem, but as soon as I closed the ring, an unrelated link went down. When I plugged in Port 2 Switch 5 > Port 1 Switch 6, Port 2 Switch 4 > Port 1 Switch 5 went down. All screws are tight (not too tight, just checked all of them) and no cables are loose.
06-08-2010 12:41 AM
I still have this problem. I don't know why the link between 4 and 5 is down; I didn't even touch that link when adding the new switch. I'm afraid that if I attempt to remove or restart Switch 6 that Switch 5 will lose connectivity.
Does anyone have any recommendations?
06-08-2010 07:19 AM
If I ran the commands:
3750-Stack#diagnostic start switch 4 test 1
3750-Stack#diagnostic start switch 5 test 1
to run the TestPortAsicStackPortLoopback test, what would happen? They're classified as non-disruptive tests, but the whole addition of a new stack member was supposed to also be non-disruptive and now it ain't working properly, so I don't really want to believe the documentation at this point.
If I run this loopback test in order to check to see if the actual stack-ports are faulty, would it cause the switches to lose data or disrupt network traffic in any way?
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