SX550-24F - Stacking issues, unreliable

[Nico.]

Hello,

Have issues with the sx550x switches (with sg550x as well but these seem to be more stable now on firmware version 2.3.5.63).

Situation is as follows, 2x SX550x switches (SW003) in stack uplinked to core switch 4500x, this over a trunk port on each switch.

after 2 months working without issue suddenly switch is unresponsive, connection to devices connected on switch 1 (master) still working but not on switch 2. Switch is unresponsive so unable to do anything but do a hard reboot of both switches.

After this switches come up again and everything is working, checking logging shows nothing.

And have anther set of these 2x SX550x (SW002) also having same issue, this is uplinked via a LAG port to the 4500x, 1 LACP interface on each switch, there I did have an error message in the log:
Error %Stack-E-STCK-EXCEP-HNDLR: Lost connection with unit 2 reason : connection timeout. Unit will be rebooted .

for this switch the ports starting flapping at this point which causes connection to the switch and everything connected to it to fail. After shutting down the slave switch unit 2 everything comes up again, restarting unit 2 and everything stays up.

Latest firmware on all the sx550x switches 2.5.87.

Disabled green power EEE and smartport as well.

Config of ports on 4500x:

CORE-01#sho run int te 1/1/15
interface TenGigabitEthernet1/1/15
description UPL.SW003master
switchport mode trunk
spanning-tree link-type point-to-point
end

CORE-01#sho run int te 2/1/15
interface TenGigabitEthernet2/1/15
description UPL_SW003slave
switchport trunk native vlan 202
switchport mode trunk
spanning-tree link-type point-to-point
end

---

CORE-01#sho run int te 1/1/5
interface TenGigabitEthernet1/1/5
description UPL_SW002
switchport mode trunk
no cdp enable
channel-group 5 mode active
spanning-tree link-type point-to-point
end

!

CORE-01#sho run int te 2/1/5
interface TenGigabitEthernet2/1/5
description UPL_SW002
switchport mode trunk
no cdp enable
channel-group 5 mode active
spanning-tree link-type point-to-point
end

!

interface Port-channel5
description UPL_SW002
switchport
switchport mode trunk
spanning-tree link-type point-to-point
end

---

Config SX550x switches:

SW003#sho run int te 1/0/24 (copper cable)
interface TenGigabitEthernet1/0/24
description UPL_CORE01
spanning-tree link-type point-to-point
switchport mode trunk
!
SW003#sho run int te 2/0/24 (fiber SFP 1Gig multi-mode)
interface TenGigabitEthernet2/0/24
description UPL_CORE01
spanning-tree link-type point-to-point
switchport mode trunk
switchport trunk native vlan 202
!
---

SW002#sho run int te 1/0/24 (fiber SFP+ 10Gig Single-mode)
interface TenGigabitEthernet1/0/24
description UPL_CORE01-te1.5
channel-group 1 mode auto
!
SW002#sho run int te 2/0/24 (fiber SFP+ 10Gig Single-mode)
interface TenGigabitEthernet2/0/24
description UPL_CORE01-te2.5
channel-group 1 mode auto
!
SW002#sho run int po 1
interface Port-Channel1
description UPL-CORE01
spanning-tree link-type point-to-point
switchport mode trunk
!

Logging on 4500x show nothing for sw003 and for sw002 you continuously see the ports flapping:

Jun 8 10:23:58.510: %EC-5-UNBUNDLE: Interface Te2/1/5 left the port-channel Po5
Jun 8 10:23:58.508: %EC-5-UNBUNDLE: STANDBY:Interface Te2/1/5 left the port-channel Po5
Jun 8 10:27:49.283: %EC-5-BUNDLE: Interface Te2/1/5 joined port-channel Po5
Jun 8 10:27:57.833: %EC-5-UNBUNDLE: Interface Te2/1/5 left the port-channel Po5
Jun 8 10:28:01.387: %EC-5-BUNDLE: Interface Te2/1/5 joined port-channel Po5
Jun 8 10:28:01.500: %EC-5-BUNDLE: STANDBY:Interface Te2/1/5 joined port-channel Po5
Jun 8 10:31:41.486: %EC-5-UNBUNDLE: Interface Te1/1/5 left the port-channel Po5
Jun 8 10:31:41.598: %EC-5-UNBUNDLE: STANDBY:Interface Te1/1/5 left the port-channel Po5
Jun 8 10:31:45.309: %EC-5-BUNDLE: Interface Te1/1/5 joined port-channel Po5
Jun 8 10:31:55.135: %EC-5-BUNDLE: STANDBY:Interface Te1/1/5 joined port-channel Po5
Jun 8 10:33:23.098: %EC-5-UNBUNDLE: Interface Te1/1/5 left the port-channel Po5
Jun 8 10:33:23.198: %EC-5-UNBUNDLE: STANDBY:Interface Te1/1/5 left the port-channel Po5
Jun 8 10:33:26.883: %EC-5-BUNDLE: Interface Te1/1/5 joined port-channel Po5
Jun 8 10:33:32.732: %EC-5-BUNDLE: STANDBY:Interface Te1/1/5 joined port-channel Po5
Jun 8 10:34:12.810: %EC-5-UNBUNDLE: Interface Te2/1/5 left the port-channel Po5
Jun 8 10:34:12.926: %EC-5-UNBUNDLE: STANDBY:Interface Te2/1/5 left the port-channel Po5
Jun 8 10:34:16.413: %EC-5-BUNDLE: Interface Te2/1/5 joined port-channel Po5
Jun 8 10:34:16.513: %EC-5-BUNDLE: STANDBY:Interface Te2/1/5 joined port-channel Po5
Jun 8 10:39:38.483: %EC-5-UNBUNDLE: Interface Te2/1/5 left the port-channel Po5
Jun 8 10:39:38.600: %EC-5-UNBUNDLE: STANDBY:Interface Te2/1/5 left the port-channel Po5
Jun 8 10:39:42.197: %EC-5-BUNDLE: Interface Te2/1/5 joined port-channel Po5
Jun 8 10:39:45.154: %EC-5-BUNDLE: STANDBY:Interface Te2/1/5 joined port-channel Po5
Jun 8 10:39:48.201: %EC-5-UNBUNDLE: Interface Te1/1/5 left the port-channel Po5
Jun 8 10:39:48.297: %EC-5-UNBUNDLE: STANDBY:Interface Te1/1/5 left the port-channel Po5
Jun 8 10:39:52.042: %EC-5-BUNDLE: Interface Te1/1/5 joined port-channel Po5
Jun 8 10:40:25.412: %EC-5-UNBUNDLE: Interface Te1/1/5 left the port-channel Po5
Jun 8 10:40:29.369: %EC-5-BUNDLE: Interface Te1/1/5 joined port-channel Po5
Jun 8 10:40:56.229: %EC-5-UNBUNDLE: Interface Te1/1/5 left the port-channel Po5
Jun 8 10:41:00.154: %EC-5-BUNDLE: Interface Te1/1/5 joined port-channel Po5
Jun 8 10:41:00.264: %EC-5-BUNDLE: STANDBY:Interface Te1/1/5 joined port-channel Po5

Hopefully somebody has an idea as these will otherwise become expensive paperweights...

[balaji.bandi]

I check as below steps :

1. Physcal connection ok ?

2. both the side using same SFP if you using Optic Module to connect.

3. is this ever worked or failing after stable running time ?

4. is the verison of code running (latest and stable ?)

if all checked and still issue raise an TAC case :

http://www.cisco.com/c/en/us/support/web/tsd-cisco-small-business-support-center-contacts.html

[Nico.]

Answer to your Q's:

1. Physical connections are ok.

2. Using same SFP+ at both sides.

3. Had been up and running for 6 months in the case of SW02 and 2 months for SW03 before problem occurred.

4. Firmware is latest (stable?) firmware form cisco support page.

    (Downloads Home/Switches/LAN Switches - Small Business/550X Series Stackable Managed Switches/SX550X-24F 24-Port 10G SFP+ Stackable Managed Switch/Switch Firmware - 2.5.7.85)

Will check to raise a TAC case as suggested.

[balaji.bandi]

as i am ware this was works many users, but  some time may have defect on the prodcts, (that can only be resolved with involvement of TAC) ?

[marce1000]

              - FYI : https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvp37139

  M.

[Rebsamen]

Hi, know am a little late but with the same problem.

Has anybody found a solution to this problem? Is this a known bug, because this problem is driving me crazy (already had to hard reboot the switch 5 times as of now)

[Nico.]

Hey, sorry for the late answer. but unfortunately no solution.

Only thing I can say with confidence, do not buy these switches. Especially not for production environment, Cisco really dropped the ball here.

Solution I used was just not to use the stacking, standard uplink and seems to be working fine atm.

You do lose the functionality of the stacking of course...

I used two 10gig ports in lacp for the uplinks between the switches.