Error, but successful boot on a C3750E

[Matt Hoppes]

I have a C3750E-24TD-S on which I just loaded new firmware.  When I boot up I see this:

Loading "c3750e-universalk9-mz.150-1.SE2.bin"...c3750e-universalk9-mz.150-1.SE2.bin: no such device

Error loading "c3750e-universalk9-mz.150-1.SE2.bin"

Interrupt within 5 seconds to abort boot process.

Loading "flash:/c3750e-universalk9-mz.150-1.SE2.bin".

But the switch runs fine.  What does this mean?

[John Blakley]

Matt,

There's probably a "boot system" line in your running config that points to an invalid file in flash. If it can't find this file, it will try to boot from the next image that it can find in flash which is why it still boots. If you remove the "boot system flash:/image" line from the running config and reload, you shouldn't have this error.

HTH,

John

[Ivan Shirshin]

Hi Matt,

The error indicates that the file path to the IOS Image in boot string is not correct. So the switch is informing you about it and either using second boot string (if you have several) or searching the flash file system for first IOS image it can find.

He succeeds on this 2nd step and boots fine.

To correct the boot string you have to check what is the issue with it. Most likely, from the outputs above, you missed to specify that file is located on flash and used something like "boot system c3750e-universalk9-mz.150-1.SE2.bin".

This should have been "boot system flash:/c3750e-universalk9-mz.150-1.SE2.bin".

You can check the current configuration with either "show boot" or "show run | i boot".

Kind Regards,
Ivan

**Please grade this post if you find it useful.

[Matt Hoppes]

That would have been my first guess too... but this is all that is in the boot section, even if I try to set a boot system:

Switch#show run | i boot

boot-start-marker

boot-end-marker

It acts like it took the boot system command, but then when I go back and show run | i boot the command isn't there.

[Ivan Shirshin]

Can you send the output of "show boot", please?

[Matt Hoppes]

witch#show boot

BOOT path-list      :

Config file         : flash:/config.text

Private Config file : flash:/private-config.text

Enable Break        : no

Manual Boot         : no

HELPER path-list    :

Auto upgrade        : yes

Auto upgrade path   :

Timeout for Config

          Download:    0 seconds

Config Download

       via DHCP:       disabled (next boot: disabled)

[Ivan Shirshin]

Would it be possible to try to add "boot system flash:/c3750e-universalk9-mz.150-1.SE2.bin", save configuration, reload and check whether error reoccurs? This behavior could also mean corrupted image of flash but you are saying it boots correctly after this error.

[Matt Hoppes]

That's the problem.  I can't add that entry.  I try and it doesn't show up in the boot section of the config.

[Ivan Shirshin · Accepted solution]

I did some search and it seems that unlike a router, a 3750 switch will not show this setting as part of the config. To see the setting you'll have to  use the "show boot" command. Did you check if the path in "show boot" was changed?

[Matt Hoppes]

So how do you change the boot path-list????

[Surya ARBY · Accepted solution]

issue the command in configuration mode; SAVE THE CONFIG (copy run start; othyerwise it may not work) and then check the output of a "show boot" or "show boot system"

[Matt Hoppes]

That did it.  Thanks.  I've been a few years out of the Cisco world, and then it was mostly only routers.

[John Blakley]

Ivan,

This is not entirely true. If the switch is not part of a stack, the boot line shows up just fine. I have older 3750s and mine show up. As far as my stack is concerned, it doesn't show under there. But, Matt, run the entry to an invalid file and then do a show boot. The file that it boots to should change to your invalid file. Then you can run the line again to the real file and notice that the file changes in show boot.

HTH,

John

[Ivan Shirshin]

Hi John,

Are you sure about that? I don't have a switch to check now but it should save boot string to ROMMON BOOT variable rather than to nvram configuration. That are seen with "show boot" in IOS:

     show boot
     BOOT path-list      : flash:filename.bin

or "set" in ROMMON:

     switch: set
     BOOT=flash:filename.bin

Even the following guide specifies:

     "The switch attempts to automatically boot up the system by using information in the BOOT environment variable. "

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_55_se/commmand/reference/cli1.html#wp11889921

Matt, changing the boot path is with "boot system ..." command but to check it you should use "show boot". Did it change after you applied the suggested command?

Kind Regards,
Ivan

**Please grade this post if you find it useful.