Cisco Switch: Upgrading Firmwares & Recovering from Failed ones !

If it ain’t broke, don’t fix it ! So true 🙂 Z@ib

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Quick notes for myself: Disclaimer! This is important!

My humble request is that kindly donot consider me as an expert on this stuff, I am NOT certified in anything Mikrotik/Cisco/Linux or Windows. However I have worked with some core networks and I read , research & try stuff all of the time. When you are enslaved by private job & working as one man army, you have to perform many task in which you are not formally trained for. So I am not speaking/posting about stuff I am formerly trained in, I pretty much go with experience and what I have learned on my own. And , If I don’t know something then I read & learn all about it.

So , please don’t hold me/my-postings to be always 100 percent correct. I make mistakes just like everybody else. However – I do my best, learn from my mistakes and try to help others

Maybe this post will help some other novice like me

Regard’s
Syed Jahanzaib

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WS-C3650-48PD

Fortunately this model have nice GUI which supports easy upgrade of firmwares , therefore I used it to upgrade to latest stable build Fuji-16.9.4

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SG300-28PP/SG500-52PP

This model also have nice GUI which supports easy upgrade of firmwares , therefore I used it to upgrade to latest stable build

https://www.cisco.com/c/en/us/support/switches/sg500-52-52-port-gigabit-stackable-managed-switch/model.html#~tab-downloads

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3750X-48T-S

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WS-C3750E-24TD

OLD version:

WS-C3750E-24TD     12.2(40)SE

Steps for Upgrade:

First setup new or use existing TFTP server, download the new firmware from

https://software.cisco.com/download/home/280831016/type/280805680/release/15.0.2-SE11?i=!pp

& copy the firmware file (.BIN format) in TFTP root folder. Now from switch console , copy the file from TFTp into switch FLASH

copy tftp: flash:

It will ask the tftp server IP, and source/destination file name, fill them up as per your local scenario

>Address or name of remote host? <IP_ADDRESS_OF_TFTP_SERVER>
>source filename? <IMAGE_NAME.bin>
>Destination filename? <IMAGE_NAME.bin>
conf t
boot system flash:<IMAGE_NAME.bin>
exit
wr
reload

after this switch will reboot , and new firmware will be overwritten.

New version:

Release 15.0.2-SE11 MD

 

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WS-C3850-24T

Notes:

With this model, I encountered few issues in upgrading 3850 switch.

• Gibralter 16.12.1 ED : 3850 / Switch was doing reboot in loop with following error

Kernel panic – not syncing: VFS: Unable to mount root fs on unknown-block(1,0)

• Fuji 16.9.4 MD : 3850 / Switch Port Orange Light issue

With this upgrade , switch booted but all ports lights runed to amber.

• Denali 16.3.9 MD : 3850 / Well tested , worked OK

Therefore I reverted back to to Denali-16.3.9 which worked fine & stable.

Steps for Upgrade:

First setup new or use existing TFTP server, download the new firmware from

https://www.cisco.com/c/en/us/support/switches/catalyst-3850-24t-s-switch/model.html#~tab-downloads

>Address or name of remote host? <IP_ADDRESS_OF_TFTP_SERVER>
>source filename? <IMAGE_NAME.bin>
>Destination filename? <IMAGE_NAME.bin>
conf t
software install file flash:cat3k_caa-universalk9.16.03.09.SPA.bin new force verbose

after this switch will ask to reload , do so to apply changes

New version:

16.3.9

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Recovering from IOS FAILED upgrade on 3850 Switch

after the Gibralter firmware upgrade , 3850 switch wen into reboot loop.

Kernel panic – not syncing: VFS: Unable to mount root fs on unknown-block(1,0)

More infor on this issue mentioned here @ https://community.cisco.com/t5/switching/catalyst-c3850-gibraltar-16-12-1-ed/td-p/3907723

After entering recovery mode , I made the situation worsen by deleting some flash files. This is how I recovered from this situation.

from the switch Management port, connect a cable directly to your laptop/desktop & assign any private IP on the system like 192.168.99.1/24. Install any free TFTP server like SOLARWINDS TFTP Server. copy the stable firmware like DENALI 16.0.3.09 in the tftp root folder.

cat3k_caa-universalk9.16.03.09.SPA.bin

Now using any terminal tool like putty, connected to switch via CONSOLE port, press MODE button while booting & entered RECOVERY mode. & issued following CMD’s

• flash_init
• mgmt_init
• set IP_ADDR 192.168.99.2/255.255.255.0
• set default_router 192.168.99.1
• emergency-install tftp://192.168.99.1/cat3k_caa-universalk9.16.03.09.SPA.bin

There was another easy method by connecting USB into usb port of switch, but since switch may not recognize most modern usb’s , therefore I had to take a long route of TFTP.

To read in more details , refere following post

http://blog.unolution.com/networking/how-to-recover-a-cisco-switch-3560x-3750x-from-boot-loader/

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Regard’s
Syed Jahanzaib