4510R+E VSS IOS Upgrade

[Carlos Aguinaldo]

Team,

What would be the best approach to upgrade our switch? Should I go for the 4-command ISSU or just change the boot variable? We prefer to copy the IOS from a USB to flash instead of TFTP.

Thanks in advance!

[Leo Laohoo · Accepted solution]

We prefer to copy the IOS from a USB to flash instead of TFTP.

Nothing wrong with copying file(s) from a USB thumbdrive.  Personally, I'd prefer this way as long as I have direct access to the appliance.  But if I don't have direct access to the appliance then TFTP is my preferred method.  

What would be the best approach to upgrade our switch? Should I go for the 4-command ISSU or just change the boot variable?

Whatever floats your boat.  Not wanting to sound like a broken record but I've responded to questions like this regarding IOS upgrade on 4500/6500 using ISSU/FSU/eFSU vs the "old fashion' method.  It all depends on how confident you are to jump and intervene if it's necessary.  

[Carlos Aguinaldo]

Thanks Leo. Just a slight clarification on the following document for upgrading SUP 7-Es on VSS.

http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-4500-series-switches/white-paper-c11-732289.html

Sorry if this is very  basic but it is my first time to upgrade a 4500 on VSS. Is it really that simple? Based on the document, here's my MOP:

1.) Copy the new software into the switch's active and standby flash

**For SUP 7-E

copy usb0:cat4500e-universalk9.SPA.03.06.04.E.152-2.E4.bin bootflash:
copy usb0:cat4500e-universalk9.SPA.03.06.04.E.152-2.E4.bin slavebootflash:

2.) Change the boot variable and save the config

conf t

no boot system flash bootflash:cat4500e-universalk9.SPA.03.04.01.SG.151-2.SG1.bin

boot system flash bootflash:cat4500e-universalk9.SPA.03.06.04.E.152-2.E4.bin

write

3.) Verify that the new software image is set to boot on next reload.

show bootvar

4.) Reload both SUPs

redundancy reload shelf

Thanks again.

[Leo Laohoo · Accepted solution]

1.  What is the config-registry value?  Sup7 & Sup8 are shipped with 0x2101 instead of 0x2102.  

2.  Before uploading the IOS into the switch supervisor cards, please check the MD5 hash value of the BIN file against the MD5 hash value found in the Cisco website. 

3.  Read the Release Notes of the IOS chosen.  There are some cases where the supervisor cards' ROMmon needs to be upgraded first. 

4.  4500 supervisor cards can support one or more boot variable string.  My recommendation is to have the first boot variable statement boot the new IOS and the second boot variable statement boot the OLD IOS.  This means that during a reboot, if the new IOS is corrupt, the switch will immediately boot the second IOS.

[Carlos Aguinaldo]

We are upgrading from 03.04.01.SG to 3.6.4E.

1.) Current config register is 0x2012. Do I need to modify this as well?

2.) Ok, noted.

3.) From the following,

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/release/note/OL_32143-01.html#pgfId-2552718

"If you are upgrading to Cisco IOS XE 3.6.0E and using Supervisor Engine 7-E or 7L-E, you must use ROMMON version 15.0(1r)SG10 or a higher version (if available)"

We are running ROM: 15.0(1r)SG7, so thanks a bunch! You saved me there.

4.) Ok, noted.

[Leo Laohoo]

1.) Current config register is 0x2012. Do I need to modify this as well?

Personally, 0x2102 is good.  

so thanks a bunch! You saved me there.

I've upgraded our Sup7E ROMmon several times.  It's all good to me.  Just make sure that after the ROMmon upgrade the bootvariable string pointing to the ROMmon file MUST BE REMOVED.

[Carlos Aguinaldo]

Do you mean this one?

Step 11 Use the delete command on the active supervisor to delete the PROM upgrade program from bootflash.

The following example shows how to delete cat4500-e-promupgrade-150_1r_SG2 image from bootflash:

Switch# delete bootflash: cat4500-e-promupgrade-150_1r_SG2

Step 12 On a redundant system, also delete the upgrade file from the standby supervisor engine.

Switch# delete slavebootflash: cat4500-e-promupgrade-150_1r_SG2

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/release/note/OL_24829.html#pgfId-178803

Just curious, why the need to delete it?

[Leo Laohoo]

Yes.  Delete the file and delete the boot variable string pointing to the ROMmon file. 

Why?  Because if you don't, the next time the chassis reboot the ROMmon file will get executed.

[Carlos Aguinaldo]

Got it. Thanks.

[Leo Laohoo]

Thanks for taking the time to rate the posts.  :)

[Carlos Aguinaldo]

You're welcome. I have two other queries though. Sorry. :)

1.) Here is a snip from one of the ROMMON upgrade guides I found here

Link:

https://supportforums.cisco.com/document/124166/how-upgrade-cisco-4500-sup7-e-sup7l-e-rommon-support-vss

So here, I see that the prompt switches from rommon 1 to rommon 2. Is this due to transferring the console cable to the "previously" standby SUP or does this happen automatically in the console output?

2.) From the same guide

Step6: This may happen automatically if the system is. You can also configure auto-boot using “boot system bootflash:cat4500-e-ios-promupgrade-150-1r-SG7” to happened boot process automatically. Be sure you write your config after this command.

I believe the complete statement for the first sentences above is:

Step6: Boot the Cisco IOS software image. This may happen automatically if the system is configured to auto-boot. You can also......

What does this mean? Do I also need to configure the boot system bootflash: command while in rommon?

Thanks again for all your help!

[Leo Laohoo]

THIS is the process I used.  Have a read of this (less confusing).

Do I also need to configure the boot system bootflash: command while in rommon?

Configure the boot variable statement in configuration mode.  

[Carlos Aguinaldo]

Ok, will refer to that DOC instead. Yes indeed, the link that I sent is definitely causing confusion. I already have a boot variable statement, but for the current IOS of course.

boot system flash bootflash:cat4500e-universalk9.SPA.03.04.01.SG.151-2.SG1.bin

So why did they use the prom file (boot system bootflash:cat4500-e-ios-promupgrade-150-1r-SG7) in the boot variable statement? Does this mean the guide is incorrect?

[Leo Laohoo]

Ok, this is how it goes ... 

The IOS upgrade needs to be split into two segments.  The first is the ROMmon upgrade and the next is the IOS upgrade. 

For the ROMmon upgrade, change the boot variable string to boot the ROMmon file.  Reboot.  This process takes about 25 heart-pounding minutes.  Once this is finish, delete the ROMmon boot variable string & the ROMmon file and then change the boot variable string to do the new & old IOS.  Reboot.