CBS 350 Switch loses partial configuration after power failure

[Greg Wake]

I'm hoping someone can point me in the right direction.

I have several Cisco CBS350 switches deployed and during a recent power outage, several of them lost parts of their configuration.  A couple lost port trunk configuration, whilst others lost their VLAN IP address.

Fortunately I run them on a VLAN 1 and another management VLAN so I can always get to them via 2 different IP addresses.  This has been my saviour.

Not sure why.....The config is always written after changes have been made.  This has happened on several occassions so I frequently log into them and do the config save to be sure.  (I've saved the config both via the WEB interface and using SSH).

Would the mirror-configuration have anything to do with this?  If I reboot the device cleanly, all is good.  It seems a sudden power outage cause strange results.

Thanks in advance.

[marce1000]

                         - What do you mean by ' mirror-configuration' ?

 M.

[Greg Wake]

On the CBS 350 switch it has a mirror-configuration.......why.....i have no idea.  Virtually no documentation on this other than it is automatically created after a period of time when there has not been any configuration changes.  So we have running, starting and mirror configuration files.

Using the Web interface you can backup the mirror configuration....which I did, and then compared to the startup and running configurations....they are all identical.

So I am at a loss as to why this odd behaviour if the power is disconnected.  Random bits of lost configuration.

[marce1000]

  - Perhaps you could show an example or a screenshot of these mirror configuration  files , anyway when saving the config check the logs for instance afterwards, make sure there are no errors reported then. It is also advisable to nearly always disable the auto smartport feature because it can decide 'to start doing things on it's own' , review this document accordingly : https://www.cisco.com/c/en/us/support/docs/smb/switches/Cisco-Business-Switching/kmgmt-2797-smartport-best-practices-CBS.html

 M.

[Greg Wake]

Many thanks....yes, on some of the switches it was on, and others it was not...different firmware versions.  Now those that were turned off just might be the same switches that DID NOT lose any of their config.  You may be onto something

I've turned it off on all switches.  Now I just have to wait for an opportune time to test.....

Many thanks for your assistance

[Christian Hamel]

Hi,

i can confirm the failure on CBS250 and CBS350 both with latest firmware...

i've only recognized in combination of VLAN an TRUNK / GENERIC Port Configuration....

Generic Ports lost their configuration ans switched back to trunk port.

Fortunatly, Cisco stores the configuration details for the different port modes access, trunk, generic... so its only one click away in the GUI... to revert the issue.

I'm not shure if its a GUI issue or also if configured via console....
Maybe the GUI is checking the Combo-Index if Basic / Advanced is used... and reverts the configuration for the VLAN?
But this is only an idea, nothing what i've tried to reproduce...
By default after Login the Mode switches back to BASIC...
My opignon, if Advanced Configuration-Options are enabled, the GUI-system must recognize this and of Basic was choosed, the must be a check / message to warn the user thant the port is configured with advanced....

if i've time i'll do some tests to reproduce the issue, also take backups...
but maybe some one can forward this to cisco development to check if there is somewhere an firmware issue...

kind regards

[Greg Wake]

Well that's good to hear that you've been able to identify this as an issue.  The times this has happened, trunk ports with specific VLAN's assigned reverted back to a standard access port, and I've lost an IP address on one of the VLAN's, which happened to be what I use to access the switches for management.  So far, those ports configured as access ports with a VLAN assigned have been unaffected.

Yep, backups for sure....I have a utility that automatically goes round to all switches and backs them up daily...it's been quite a life saver!  

[Krlitos]

Hi, can you comment on which utility you use to make daily backups? Because I have the same problem.  

[Christian Hamel]

Hi,

please try to disable the Smart Port Feature / Function for the whole switch…

maybe you need to reconfigure some ports where the smartport scheduler has applied his roules…

but after this the configuration isn’t altered after reboot by “smartport”

[KJK99]

Those switches have running and startup configuration. I guess that's standard on CISCO switches. The running configuration will be lost after a power failure. If you make any configuration changes and you want them to be preserved after a switch restart, make sure you save that configuration. 

[Christian Hamel]

I Know…

but if i press the Save Button (blinking Disc Icon) normally the config is written to Startup… so it seems Not to be a User failure 

[Greg Wake]

Yep, thought that was my mistake the first time round but this has happened several times.  I usually do a save from within the GUI, and a save from the command line....and still have the problem.  

[Christian Hamel]

So... short Update,

after a closer look in the start-up config backup...

so what i've described in my previous post is a SMART-PORT "feature"
after disabling SMART-PORT
or disabling 2 SMART-PORT macros 

macro auto processing type ip_phone disabled
macro auto processing type ip_phone_desktop disabled

the port is untouched...

so conclusion....
disable SMART-PORT for all Ports (as Firmware-Default) and let the admin decide if he would like use cool detection features...


i'll check if there is the same "detection" issue on another customers CBS, there is a similar problem but on the SWITCH's Uplink LAG (loosing TRUNK and get switched to ACCESS)

[saadaldin2001]

  I also need a solution for this problem with (CBS350-24P-4G 24-Port Gigabit PoE Managed Switch) Version 3.0.0.69, those switches lost some of their configurations after reboot or electric power disconnect.

[marce1000]

@saadaldin2001 ->   https://www.cisco.com/c/en/us/support/web/tsd-cisco-small-business-support-center-contacts.html

 M.