PIX 6.3 - capture command

Aug 14, 2005 3 Replies

255.255.255.128 eq 5222
255.255.255.128
255.255.255.128 eq 5222
255.255.255.128

Actually, the third line doesn't make sense... "eq" is not a valid keyword with ICMP, and there's no such thing as an ICMP type 5222 packet.

Hello group members,



I have two PIX



PIX-A: 195.238.10.19 PIX-B: 212.217.89.23



Behing, Private LAN



PIX-A: 192.168.10.0/25 PIX-B: 192.168.20.0/25



I need a VPN between those, so, I've defined a no-nat access-list



access-list no-nat-pix-a permit ip 192.168.10.0 255.255.255.128



192.168.20.0 255.255.255.128 access-list no-nat-pix-a permit ip 192.168.20.0 255.255.255.128
192.168.10.0 255.255.255.128

and, an access-list to bound to what to encrypt to get to pix-b



access-list to-pix-b permit tcp 192.168.10.0 255.255.255.128



192.168.20.0 255.255.255.128 eq 5222 access-list to-pix-b permit tcp 192.168.20.0 255.255.255.128
192.168.10.0 255.255.255.128 access-list to-pix-b permit icmp 192.168.10.0 255.255.255.128
192.168.20.0 255.255.255.128 eq 5222 access-list to-pix-b permit icmp 192.168.20.0 255.255.255.128
192.168.10.0 255.255.255.128

It works ok,



I use the "capture" command to check if the VPN is going ok. Like



pix-a#(config)capture snoopy interface inside buffer 10000 circular



using PDM, I redirect the flow to my browser.



I my web browser using this capture command, I need to filter only what is going between the host 192.168.10.10 and remote host 192.168.20.15



How do I achieve it? It looks I need to create a third access-list and apply it against the capture command.



I've tried, I can't get it.



Can anybody light it?



Thank you very much,



Amaury



In article , Amaury Ronflard wrote: :I have two PIX

255.255.255.128 eq 5222
255.255.255.128 eq 5222
255.255.255.128

The third and fourth lines duplicate the first and second.

You should only write the ACL in one direction, as if the data is going out of the local machine towards the remote machine. The ACL will automatically be matched in reverse for the remote traffic.

If you were to reverse the second line, the result would be a superset of the first, leaving the first unnecessary. I suspect you are trying to account for dynamic source ports and that the second line is actually a to-pix-a entry. If so then if you are going to include a specific port number in that first to-pix-b line, then you should exactly mirror it on b,

access-list to-pix-a permit tcp 192.168.20.0 255.255.255.128 eq 5222

192.168.10.0 255.255.255.128

Using a specific port number on an crypto map ACL will get you a warning about loss of efficiency. Earlier PIX versions prohibitted using port numbers entirely.

:I use the "capture" command to check if the VPN is going ok. Like

:I need to filter only what :is going between the host 192.168.10.10 and remote host 192.168.20.15

:How do I achieve it? It looks I need to create a third access-list and :apply it against the capture command.

Right.

I have evidence that the capture ACL is -not- automatically read in reverse, so try

access-list capture10_15_acl permit host 192.168.10.10 host 192.168.20.15 access-list capture10_15_acl permit host 192.168.20.15 host 192.168.10.10 capture c10_15 access-list capture_10_15_acl

In article , Walter Roberson wrote: :capture c10_15 access-list capture_10_15_acl

Sorry, you'll probably need to add the 'interface' specification to that.

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