3640 booting Large IOS (> 32MB)

In article , snipped-for-privacy@alpensea.com (haydude) writes: | Hi Everyone, | | I found some messages on this subject, and search for docs on | Cisco.com, but to no help at all. | | I am trying to tftp boot one of those large >32MB enterprise images | that do not fit in any flash, but without success.

You probably won't have much luck with tftp; use rcp or ftp (I use the former).

| Could anyone post the correct step-by-step procedure to configure the | router to boot such an image from tftp successfully? Could anyone | indicate which image we need to have in flash in order to have a | successful tftp boot without running out of memory?

I use io3 12.2(40) because it is small and new enough to recognize most hardware. Note that if this is not the first image in flash you will have to set BOOTLDR in the monitor. I actually keep the

12.2(40) used as rxboot on a PCMCIA card so I have room for 12.4(13a) in main flash as a fall back.

Dan Lanciani ddl@danlan.*com

We had/have fun with this issue on 28xx hardware: the regular images are way over 32MB, yet the ROMMON does not implement the blksize extension...

Its mainly a TFTP issue: plain standard TFTP w/o extensions has a protoco= l inherent filesize limit of 32MB since the standard block size of TFTP is

512 Bytes and the sequence number field in TFTP is only 16 bits wide therefore you can only transfer 2^16-2 blocks of 512 bytes each -> roughl= y 32MB.

There are certain TFTP extensions that help overcome this limit ("blksize"). The only problem is: these are not implemented in ROMMON and Cisco does not plan to implement it (result of a case we had open with Cisco), at least not on 28xx hardware.

I think your options are:

- find a tftp server that has no problem transfering files >32MB without the blksize extension (thereby violating the TFTP protocol)

- Using a boot-helper image

- Use something else than TFTP for transfer (might not work on the 3640)

Ciao Chris

--=20 All diese Momente werden verloren sein in der Zeit, so wie Tr=E4nen im Re= gen Dipl-Ing (FH) Christian 'Dr. Disk' Hechelmann IRC: DrDisk GPG Fingerprint: 53BF634B 28326F92 79651A15 F84ABB55 4F068E4E Ich finde, scharfe Waffen und "Feuer nach eigenem Ermessen" sollte zum Adminjob dazugeh=F6ren. [Lars Marowsky-Bree in d.a.s.r]

The tftp original protocol has a 32MB limit (extended in RFC 2437). My guess is your client still has this limitation. Use ftp (much faster than tftp) or here's a free Windows client that doesn't have this limitation...

alan