SG300-20 - Problems with Forwarding and Learning MACs until Write

[jeff-rogers]

I have an SG300-20 and started having problems a few weeks ago.  Primarily the problem is related to rebooting systems, waking systems from sleep, or any other activity such as speed/duplex changes on the host that cause the host NIC to cycle.  Regardless of how the host NIC "goes down", when the host NIC "turns up" it shows connected on the host and switch, but the SG300 refuses to learn the MAC.  The only remedy seems to be the write command.  Immediately after the write command is issued there is delay from 0 to a few seconds, then L2 connectivity returns.

Also, a new problem cropped-up during testing after changing the mode to "route."  If I reload the switch it stops forwarding all traffic until a write command is issued.

Anyone see these symptoms and have a solution?

Thanks,

Jeff

[Tom Watts]

Jeff, I tried a second time as well. I had noticed during my first time I hit "enter" several times because I like to watch my screen scroll. But regardless, it made no difference for me.

switch0d8210#reload------- ----------

You haven't saved your changes. Are you sure you want to continue ? (Y/N)[N] Yf:b9:b2:91:40       0         self                                           

This command will reset the whole system and disconnect your current session. Dotal number of entries: 0                         

  VLAN    Interface     IP

you want to continue ? (Y/N)[N] Ystatus                           

Shutting down ...                

Shutting down ...--------- -------

Shutting down ...---------- ------

Resetting local unit                   

**************************************************9140#            

switchb29140#delete startup-con

*****************  SYSTEM          

Delete startu

Boot1 Checksum Test........................        

switchb29140#            

                    #                               #reset the device right after that. It is highly recom

                   ###                             ###                                         

backup it b

                   ###                             ###                                               

switc

                   ###                             ###b29140#reload                  

You haven't saved you

            #      ###      #               #      ###      #                                                            

           ###     ###     ###             ###     ###     ###nnect                                                       

   ###     ###     ###     ###     ###     ###     ###     ###     ###..PASS                                                     

Flash Im

    #       #      ###      #       #       #      ###      #       #                             

BOOT Software Version 1.2.0.12 Buil

                   ###                             ###                           

                    #  

                   ###                             ###                          

                   ###   

                    #                               #                           

   ###     ###     ###     ###  

          #########   ###   ##    ###    #########    #########                                          

   ###     ###    

            #######   ###    #######       #######      #####                                                          

Networking device with Marvell ARM CPU core. 128 MByte SDRAM. ##                                                         

100%    

Decompressing SW from image-1                            

100%

OK 

Running from RAM...#######       #####

GPIO ID is 3           

Module type is 10                

Device ID 0xdff411ab    #########   ###

*********************************************************************                            

         ###          ###    ####     

*** Running  SW  Ver. 1.3.5.58  Date  10-Oct-2013  Time  17:15:41 ***                  

         ###          ###      ###      ###     

*****************************************************************            

Dram first PTR is  : 0x1780000##    #######       #######  

Dram second block size is  : 4096K bytes                           

Networki

Dram second PTR is  : 0x7C00000ore. 256 MByte SDRAM.         

Flash size is: 16M                 

................................................................................                                                       

MAC Address   :  e0:5

................................................................................RETURN or Esc. to abort and enter prom.                                        

................................................................................

100%    

Decompressing SW from image-2                            

100%   

------------------------------------

HW version is V01                

Tapi Version: v1.9.6e0:5f:b9:b2:91:40  

Core Version: v1.9.6             

Dram

10-Oct-2013 17:16:18 %INIT-I-InitCompleted: Initialization task is completed08896K bytes                                        

Dram first PTR is  : 0

10-Oct-2013 17:16:33 %Entity-I-SEND-ENT-CONF-CHANGE-TRAP: entity 4096K bytes                                       

Device 0: GT

This may take a few minutes, depending on the key size.------------------------------                        

10-Oct-2013 17:16:34 %Environment-I-FAN-STAT-CHNG: FAN# 1 status changed - opera  

------------------------------------                                   

19

tional.2 17:57

The SSH Server is generating a default DSA key.configuration c                               

This may take a few minutes, depending on the key size.rap.          

19-Jul-2012 17:57:51 %INIT-I-InitComple

The SSH Client is generating a default DSA key.ode.                                          

This may take a few minutes, depending on the key size.CK-CFG-CHNG: Configuration changed: chain             

10-Oct-2013 17:18:23 %SSL-I-SSLCTASK: Starting autogeneration of self-signed cer..............................PASS                                             

tificate - 1024 bitssum Test............

Generating RSA private key, 1024 bit long modulus                         

Flash Image Validatio

10-Oct-2013 17:18:31 %SSL-I-SSLCTASK: Autogeneration of self-signed certificate      

BOOT Software Version 1.3.5.06 Built  21-Jul-2013  15:             

was successfully co                 

switch0d8210#           

User Name:        ##

Detected speed: 115200       ###           

User Name:cisco              

Password:*****       #     

Please change your password from the default settings. Please change the passwor                    

           ###     ###     ###             ###     ###   

d for better protection of your network. Do you want to change the password (Y/N     ###     ###      #      ###     ###     ###      #                        

)[Y] ?N      

switch0d8210#show mac address-table    ###     ###     ###     ###   

Aging time is 300 sec   ###              

  Vlan        Mac Address         Port       Type   

switch0d8210#     #      #

switch0d8210#10-Oct-2013 17:19:08 %LINK-W-Down:  gi3                                

10-Oct-2013 17:19:08 %LINK-W-Down:  Vlan 1                                         

switch0d8210#          ###

switch0d8210#show mac address-table                                  

Aging time is 300 sec              #     

  Vlan        Mac Address         Port       Type                           

   1       64:31:50:1c:50:d3      gi3      dynamic

switch0d8210#10-Oct-2013 17:19:16 %LINK-I-Up:  gi3, aggregated (1)

10-Oct-2013 17:19:16 %LINK-I-Up:  Vlan 1, aggregated (1)

10-Oct-2013 17:19:21 %STP-W-PORTSTATUS: gi3: STP status Forwarding, aggregated (

1)

10-Oct-2013 17:19:31 %LINK-W-Down:  gi3, aggregated (1)

10-Oct-2013 17:19:31 %LINK-W-Down:  Vlan 1, aggregated (1)

10-Oct-2013 17:19:36 %LINK-I-Up:  gi4

10-Oct-2013 17:19:36 %LINK-I-Up:  Vlan 1, aggregated (1)

10-Oct-2013 17:19:41 %STP-W-PORTSTATUS: gi4: STP status Forwarding

switch0d8210#

switch0d8210#show mac address-table

Aging time is 300 sec

  Vlan        Mac Address         Port       Type

-------- --------------------- ---------- ----------

   1       00:26:0b:0d:82:10       0         self

   1       64:31:50:1c:50:d3      gi4      dynamic

switch0d8210#10-Oct-2013 17:19:50 %LINK-W-Down:  gi4

10-Oct-2013 17:20:53 %INIT-I-Startup: Warm Startup

switch0d8210#

switch0d8210#show mac address-table

Aging time is 300 sec

  Vlan        Mac Address         Port       Type

-------- --------------------- ---------- ----------

   1       00:26:0b:0d:82:10       0         self

switch0d8210#

-Tom
Please mark answered for helpful posts

[jeff-rogers]

Tom,

I understand that you cannot recreate the problem - I really didn't think you would be able too, not with a working switch.  If you were able to recreate this problem your Cisco TAC phones would light up like a Chrismas tree, because noone likes a switch that won't switch, and a fix would be issued.

My switch however, does show this problem and since we are both using the same model switch and firmware version, there must be a defect with my switch.  The reason I say this is because, given a switch, any switch, with the latest firmware and a factory reset, when the switch boots, it should learn MACs and forward traffic without having to save the config - learning MACs and forwarding traffic is what a switch does.  But for some reason I feel that you and TAC are missing this quintessential point:  MY SWITCH DOES'T ALWAYS SWITCH.

Because my switch has this problem (not switching) I would expect Cisco to replace/repair it under warranty.  I have told TAC of this expectation, but they insist on troubleshooting (turn on STP, turn off STP, etc) rather than realize that a switch that won't learn MACs isn't a switch and that it needs to be replaced/repaired.

Now I will ask you the same question I have asked TAC, twice, how do I get a replacment or a repair?

Thanks,

Jeff

[jeff-rogers]

Tom,

Sorry, for some reason I thought you were with Cisco Support.  Not sure why I thought that, but thanks for trying to help and sorry I vented on you - I really thought you were Cisco Support.

Sorry,

Jeff

[cindy toy]

Hi Jeff,

Did you receive a Service Request number when you called the Cisco Small Business Support Center (http://www.cisco.com/en/US/support/tsd_cisco_small_business_support_center_contacts.html)?

If so, can you private message me the number and I will check the status for you.

Regards,
Cindy Toy
Cisco Small Business Community Manager
for Cisco Small Business Products
www.cisco.com/go/smallbizsupport
twitter: CiscoSBsupport

[jeff-rogers]

Problem FIXED!!!!

After getting no support from Cisco except three emails with basic troubleshooting garbage, and having a ticket open with their TAC for more than eight days,  I bought a new switch and it works perfectly.  Unfortunately for Cisco it is not a Cisco switch.

I bought a N.E.T.G.E.A.R  GS728TP !!!!  And it solved my problem with the Cisco switch.  The GS728 learns MAC addresses and switches, but the Cisco switch does not switch - go figure....

[gayvoronskiy]

Have the same problem. Switch works only after "write" command.

Also I'm running the latest firmware and bootloader.

It's too bad that there no solution with this switches. I have 12 of them.

[christian.wes]

Hi Alexandr,
Do You have this issue with all of your switches?
What is after you made a write command, how long will it last till the Problem comes again?
In my Case the switch did work after Write command but with poor performance and after a few hours the problem came again...


Sent from Cisco Technical Support iPad App

[gayvoronskiy]

Hi Christian!

Sorry for late response.

For me it's hard identify problem because we installed switches in branches in 150 miles or more from HO.

Problem appears after switch restarts. And every morning. Maybe at night there are no power in branches, maybe not.

My network topology in branch:

Internet cable -> Cisco 881 Router -> Cisco SG300 Switch. Pretty simple.

Router plugged into 17th port on switch. And mostly it has not problem with mac learning.

So I can connect to switch from HO via SSH or HTTP and make "write" command.

Sometimes switch become working after hour or more after restart.

For today problem appeared again and I had no connection to switch.

Router was fine and it showed that fe0 and vlan are up. Cable is good and plugged properly.

After 1 hour switch become reachable. When I connect to switch I saw that it learned only router's mac address (Port 17). I made "write" command and it learned other mac addresses of my PCs in the network.

[jimgrumbles]

I'm planning to get in touch with Cisco sometime today or tomorrow but has anyone else seen this as well?  I put this switch into use early January of 2014.  I'd say this probably started showing up back in July or August of 2014.  Various firmware upgrades/downgrades have not worked.  I can repeatedly kill the network connection on a port and then try to bring the device back up but it will not learn/show the MAC address for that port until I issue the write command.  I even cleared the entire table once and all devices lost network access until I was forced to reboot it.  I tried various ping/ARP commands to force try to get the switch to pick up and learn a MAC address before rebooting but it just wouldn't work.  Disabled all Green/EEE settings as well as SmartPort.  I've got a collection of configurations beginning in January when there was no issue like this and tried those settings as well.

[jimgrumbles]

It looks like I'll be taking the same route as Jeff and purchasing a Netgear managed switch to replace my SG300-20.

[Aleksandra Dargiel]

Hi Jim,

I am really sorry to hear that but I must admit that this either hardware related issue or very specific to the whole network setup. I have never seen such a problem before unless there was a loop.

Regards,

Aleksandra

[jayjay1988]

I have now the exact same issue with a SG200-26p switch.

Since I got it from ebay, there is no warrenty either but the unit worked for 2 months flawlessly. I can pretty much date the beginning of the hassle to a evening where we had a short power outage. Since then and even after factory resetting and reflash firmware the switch needs copying startup-config to running-config (doesn't have a cli, crap anyways) after every ethernet interface state change to recognize.

The sfp ports seem to be unaffected by that and serve fine.

Sadly the conclusion must be for now: Don't ever buy cisco devices again.

Seems to be either the hardware or the firmware are out of control. Cisco doesn't seem to be able to provide solid (working) gear.