On Mon, Jul 08, 2013 at 09:35:02AM +0300, Javor Kliachev wrote:

Hello,

I'm wondering, is there any way to configure following example to single  
rule only.

if bgp_path ~ [= * 100 * =] then return false;
if bgp_path ~ [= * 200 * =] then return false;
if bgp_path ~ [= * 300 * =] then return false;
if bgp_path ~ [= * 400 * =] then return false;

On this way, If we want to filter many ASs, it seems that we should  
generate too much rows.

Well, you could replace that with this:

    if 10 ~ bgp_path then return false;

which is probably slightly faster, but you still need all the rows.
If you would test just for last (or first) ASN, you could use:

    if bgp_path.last ~ [10, 20, 30, 40, ... ] then return false;

Perhaps we should implement this:

    if bgp_path ~ [10, 20, 30, 40, ... ] then return false;

(i.e. check every ASN from bgp_path against set of numbers) That would
be simple to implement, consistent with our filtering features for
community lists and works fast for a large sets of ASN.

We don't support full regular expressions for bgp_path matching, just the
shell-like wildcard patterns.