Need process for updating IOS on Cisco CISCO2911

[ngaitan]

gateway router has a problem with IOS and needs to be upgraded in order to address two issues.
First is Tacacs integration which will cause CPU to hug the box to 100% cycle. Second the process leaks memory and will stop the router from functioning.

I haven't done an IOS upgrade before - where can I find the steps to do this? Also

The current bug is here

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCuc37272

Is the recommended version c2900-universalk9-mz.SPA.155-3.M7.bin ?

The current version is15.1(4)M4

https://software.cisco.com/download/home/282774227/type/280805680/release/15.5.3M7

[Georg Pauwen]

Hello,

c2900-universalk9-mz.SPA.157-3.M3.bin is indeed the recommended IOS.

Upgrading is simple: use TFTP to load the image into flash, then use the steps below:

2911(config)#boot system flash c2900-universalk9-mz.SPA.157-3.M3.bin
2911(config)#write mem
2911(config)#exit
2911#reload

[ngaitan]

Thank you!
Can I do the tftp copy over Putty connection or does it require console connection?

[Georg Pauwen]

Hello,

Putty requires a console connection, but you better use a TFTP server, such as the one below (free). Just connect the router to your PC.

http://tftpd32.jounin.net/

[ngaitan]

Can I do the tftp copy over Putty connection or does it require console connection?

[Richard Burts]

Perhaps we have some confusion about terms. In this discussion I believe that we are talking about doing a tftp transfer. A tftp transfer uses UDP packets to transfer a file from a tftp server to the router. So a tftp transfer takes place between the router and the server. Can we verify that you do have a device in your network that has software to act as a tftp server? And can we verify that you have a copy of the new IOS image on that device? And can we verify that there is IP  connectivity between the router and the tftp server?

You are also asking about putty. putty does not actually do the tftp transfer. putty is used to allow access to the router from your PC. putty does support a connection from your PC to the console port of the router (assuming that you have the appropriate cable to connect the router console to your PC). putty also allows you to use telnet or SSH to access the router. It does not matter which way you access the router using putty. The main thing is that you need to establish a session to the router. And from that session on the router you enter the commands to do the tftp transfer.

HTH

Rick

[ngaitan]

Hi Rick

I have SolarWinds tfp server installed and configured on my laptop which is connected to my office network. I have loaded the bin file on it.

The router is not near me but located in my cage at my primary DC

[Jon Marshall]

You just need network connectivity between your TFTP server and the router ie. can the router ping the TFTP server ? 

Jon

[ngaitan]

Yes

SAUCPRI-01>ping 10.75.30.118
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.75.30.118, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 16/65/92 ms

[Jon Marshall]

So login to router then - 

copy tftp flash: 

fill in the server IP and filename then follow Georg's instructions. 

Jon

[paul driver]

Hello

Just like to add, You need to make sure the new ios is compatible with the dram/flash memory you currently have running on the router as sometimes a new ios requires extra memory to run.

Also you need to check that you have enough space to accommodate both IOS files at the same time because sometimes when you try to download a new ios file the transfer can fail because there isnt enough space on the router to have two ios files at the sametime.

show version

Once you have downloaded the new ios, I would suggest you verify it prior to using it just in case it hasnt corrupted on download.

verify flash:newios.bin

At this point as stated by others you need to specify the rtr to boot to the new ios, However you may already have a boot system statement for the old ios configured, if this is the case then you need to remove that old statement and add a new one pointing to the new ios and then add a second statement for the old ios just in case for some reason the new ios fails.

no boot system
boot system flash:newios.bin
boot system flash:oldios.bin

wr

Once you have successfully reloaded the rtr and the new ios is running smoothly, you can remove the old boot system statement and delete the old ios.bin file from flash.

no boot system flash:oldios.bin
delete flash:oldios.bin
wr

[ngaitan]

Thank you!
This was the output

Loading c2900-universalk9-mz.SPA.157-3.M3.bin from 10.75.3.23 (via GigabitEthernet0/0): !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 110655660 bytes]

110655660 bytes copied in 1487.016 secs (74415 bytes/sec)

SAUCPRI-01#
SAUCPRI-01#
SAUCPRI-01#verify flash:c2900-universalk9-mz.SPA.157-3.M3.bin
Starting image verification
Hash Computation: 100% Done!
Computed Hash SHA2: 13E21A85C1122150C42F9392F4EE94D2
281DF4EA77D6F7C194607CF4CE355CA4
55E0CF87075E78E290F0F9E01B3DAAB4
1B4C9FB0B40616CE9E94E7A0B5BB0A5D

Embedded Hash SHA2: 13E21A85C1122150C42F9392F4EE94D2
281DF4EA77D6F7C194607CF4CE355CA4
55E0CF87075E78E290F0F9E01B3DAAB4
1B4C9FB0B40616CE9E94E7A0B5BB0A5D

CCO Hash MD5 : 13F82FB6F3C53B89D1280986DEEDA3A9
Digital signature successfully verified in file flash0:c2900-universalk9-mz.SPA.157-3.M3.bin

[Richard Burts · Accepted solution]

You have successfully copied the new image into flash. Now you probably have (at least) two image files in flash. So you need to be sure that when you boot it will use the new image. Check the running config and see if there is a boot system command. If there is it would point to the old image. So update it to point at the new image. (When I do this type of update I frequently put in boot system commands for each image, placing the boot command for the new image first and the old image following. This will attempt to boot the new image and if there is some problem will boot the old image - sort of insurance) If there is not an existing boot system command then you should configure one for the new image (and perhaps one for the old image following it - just in case). When you have updated the config be sure to save the changes to startup. Then reboot and when it comes up verify that you are using the new image.

HTH

Rick

[Leo Laohoo · Accepted solution]

Copy the IOS into the router, compare the MD5 hash value, change the boot variable string, don't forget to check the config-registry (must be 0x2102), save the config and reboot.