[c-nsp] Re-pack IOS

[Richard A Steenbergen]

On Wed, Jul 29, 2009 at 01:19:16PM +0400, Aleksandr Gurbo wrote:
> On images for 26xx series it is possible re-pack IOS, you can try
> yourself. I don't know about re-pack operations on images for
> 28xx/38xx/76xx series, may be new degree of protection or new methods
> of compression are used.

Sure, IOS is IOS is IOS, the same techniques apply.

-rw-r--r--  1 root  code  132978980 Jul 29 08:34 c7600s72033-advipservicesk9-mz.122-33.SRD2a.bin
-rw-r--r--  1 root  code   65403172 Jul 29 08:38 c7600s72033-advipservicesk9-mz.122-33.SRD2a-lan.bin

The later image has had all the SIP/SPA and FlexWan type images removed,
LAN cards only. You can reduce your boot time on the 6500/7600 platform
by about 90-100 secs (depending on file size) if you can strip out the
unnecessary images and make it fit onto the old 64MB linear bootflash
rather than the modern ATA flash. The linear flash reads at 2MB/s while
the ATA flash only reads at 1MB/s, so you reduce the "read the image
into memory" time from 132 secs to 32 secs in the example above. This
has been discussed on this list many times, search the archives. :)

-- 
Richard A Steenbergen <ras at e-gerbil.net>       http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)