Pix 501 cant ping outside 1

[sevendcruz]

Pix 501

I'm able to surf the web but not able to ping out from worksatations, do I have to allow icmp to the outside or am I missing something?
I'm also able to ping out from the pix.
Thanks


: Saved
: Written by enable_15 at 10:04:44.700 UTC Fri Apr 18 2003
PIX Version 6.2(2)
nameif ethernet0 outside security0
nameif ethernet1 inside security100
enable password
passwd
hostname pixfirewall
fixup protocol ftp 21
fixup protocol http 80
fixup protocol h323 h225 1720
fixup protocol h323 ras 1718-1719
fixup protocol ils 389
fixup protocol rsh 514
fixup protocol rtsp 554
fixup protocol smtp 25
fixup protocol sqlnet 1521
fixup protocol sip 5060
fixup protocol skinny 2000
names
pager lines 24
interface ethernet0 10baset
interface ethernet1 10full
mtu outside 1500
mtu inside 1500
ip address outside 66.x.x.164 255.255.255.248
ip address inside 192.168.4.1 255.255.255.0
ip audit info action alarm
ip audit attack action alarm
pdm history enable
arp timeout 14400
global (outside) 1 66.x.x.165
nat (inside) 1 0.0.0.0 0.0.0.0 0 0
route outside 0.0.0.0 0.0.0.0 66.x.x.161 1
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 rpc 0:10:00 h323 0:05:00 sip 0:30:00 sip_media 0:02:00
timeout uauth 0:05:00 absolute
aaa-server TACACS+ protocol tacacs+
aaa-server RADIUS protocol radius
aaa-server LOCAL protocol local
http server enable
http 192.168.4.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server community public
no snmp-server enable traps
floodguard enable
no sysopt route dnat
telnet 192.168.4.0 255.255.255.0 inside
telnet timeout 5
ssh timeout 5
dhcpd address 192.168.4.2-192.168.4.10 inside
dhcpd dns 204.x.x.10 204.x.x.10
dhcpd lease 3600
dhcpd ping_timeout 750
dhcpd auto_config outside
dhcpd enable inside
terminal width 80

 

[yizhar]

HI.

> I'm able to surf the web but not able to ping out from worksatations, do I have to allow icmp to the outside or am I missing something?

Yes.
Unlike TCP and UDP, the pix does NOT have stateful handling of ICMP.
So your echo request is passed in the outbound direction, but the echo reply coming back is blocked at the pix.

The newer Pix version 6.3 OS adds some support for ICMP, but as far as I've read it does not handle "echo".

http://www.cisco.com/univercd/cc/td/doc/product/iaabu/pix/pix_sw/v_63/63rnotes/pixrn63.htm#71785

So you have 2 choices:
1) Keep the configuration as is, and simply don't use ping to test the network. TCP (http, telnet, etc) can be used instead.
2) Permit "echo reply" on the outside interface:
access-list fromoutside permit icmp any any echo-reply
access-group fromoutside in interface outside

Read here - "Testing Connectivity":

http://www.cisco.com/univercd/cc/td/doc/product/iaabu/pix/pix_sw/v_62/config/bafwcfg.htm#997560

And here:

http://www.cisco.com/univercd/cc/td/doc/product/iaabu/pix/pix_62/cmdref/ab.htm#1067755

Bye


Yizhar Hurwitz

http://come.to/yizhar

http://teachers.sivan.co.il/yizhar

 

[sevendcruz]

Yizhar, Thanks for the detailed responce, your explanation was very useful.

 

[polharris]

Add an access-list like that :
access-list 100 permit icmp any any echo-reply
and put the access-list on the interface outside like that :
access-group 100 in interface outside

You can ping from your lan to Internet, but not from internet to your Firewall.