[c-nsp] WCCP Layer 2 redirection on 7206

[Lincoln Dale (ltd)]

> Can you confirm that WCCP L2 forwarding with mac rewrite (which is of
> course preferred over GRE forwarding), is actually a supported feature
> in the 12.2S train - say c7200-p-mz.122-18.S9.bin, or a 12.2(25)S
image
> ?   This doesn't seem to show up in feature navigator, so its unclear
in
> which version it was introduced.  My impression is that it was only
> supported on the Cat6500 platform.

yes.

WCCP with L2 rewrite actually made it into 12.0S (so by rights will be
in 12.2S).

what is specific to the cat6k is WCCP with Hash Mask support (an
alternate method of mapping traffic).  the distinction here is that
certainly L2-rewrite vs GRE-encapsulation results in less CPU
utilization, but on h/w switching platforms like cat6k, Hash Mask means
the entire process can be in h/w (we didn't have XOR hashing in h/w at
the time, hence the invention of the hash mask method).

it is a shame Feature Navigator doesn't explicitly list all these
permutaions (GRE vs L2 rewrite and XOR vs Hash Mask methods).
note however that not all vendors' caches support all of these
permutations.  best you check with your caching vendor.


cheers,

lincoln.