how to PING into inside interface of PIX 515E version 6.3(4)

nhuongpham · ‎04-08-2005

Dear Sir/Madam,

I have network as follows :

PC1------inside-PIX-ouside ------PC2

PC1 ip address 1.1.1.2

inside ip address 1.1.1.1

outside ip address 192.168.100.249

PC2 ip add 192.168.100.101 - default gateway 192.168.100.249.

now from PC2 I can PING to Outside interface but I can't PING to inside or PC1, althought from PIX I can PING to PC1 :

PIX Version 6.3(4)

interface ethernet0 auto

interface ethernet1 auto

interface ethernet2 auto

nameif ethernet0 outside security0

nameif ethernet1 inside security100

nameif ethernet2 DMZ security50

enable password 8Ry2YjIyt7RRXU24 encrypted

passwd 2KFQnbNIdI.2KYOU encrypted

hostname pix

domain-name tun.edu.vn

fixup protocol dns maximum-length 512

fixup protocol ftp 21

fixup protocol h323 h225 1720

fixup protocol h323 ras 1718-1719

fixup protocol http 80

fixup protocol rsh 514

fixup protocol rtsp 554

fixup protocol sip 5060

fixup protocol sip udp 5060

fixup protocol skinny 2000

fixup protocol smtp 25

fixup protocol sqlnet 1521

fixup protocol tftp 69

names

access-list 100 permit icmp any any

pager lines 24

mtu outside 1500

mtu inside 1500

mtu DMZ 1500

ip address outside 192.168.100.249 255.255.255.0

ip address inside 1.1.1.1 255.0.0.0

ip address DMZ 192.168.2.1 255.255.255.0

ip audit info action alarm

ip audit attack action alarm

pdm history enable

arp timeout 14400

access-group 100 in interface outside

timeout xlate 3:00:00

timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 rpc 0:10:00 h225 1:00:00

timeout h323 0:05:00 mgcp 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 TACACS+ max-failed-attempts 3

aaa-server TACACS+ deadtime 10

aaa-server RADIUS protocol radius

aaa-server RADIUS max-failed-attempts 3

aaa-server RADIUS deadtime 10

aaa-server LOCAL protocol local

http server enable

no snmp-server location

no snmp-server contact

snmp-server community public

no snmp-server enable traps

floodguard enable

telnet timeout 5

ssh timeout 5

console timeout 0

terminal width 80

Cryptochecksum:41bb422b602c6f8aedbfb366f607665b

Help me pl ! Thanks & Regards,

Patrick Iseli · ‎04-08-2005

Ping is not a stateful protocol. To allow pings from the inside to the outside interface you need to create an access-list. If you want to ping the same interface that you are physicly connected you need to configure the "icmp" command. See examples bellow.

example:

See: Handling ICMP Pings with the PIX Firewall

http://www.cisco.com/en/US/products/hw/vpndevc/ps2030/products_tech_note09186a0080094e8a.shtml

The PIX and the traceroute Command

http://www.cisco.com/en/US/products/hw/vpndevc/ps2030/products_tech_note09186a00800e9312.shtml

examples:

Traveroute

Microsoft:

access-group 101 in interface outside

access-list 101 permit icmp any host YourPublicIP unreachable

access-list 101 permit icmp any host YourPublicIP time-exceeded

access-list 101 permit icmp any host YourPublicIP echo-reply

UNIX:

access-group 101 in interface outside

access-list 101 permit icmp any host YourPublicIP unreachable

access-list 101 permit icmp any host YourPublicIP time-exceeded

ICMP command example

icmp deny any outside

icmp permit any echo-reply outside

icmp permit any echo-reply inside

icmp permit host 192.168.1.30 echo inside

icmp permit host 192.168.1.31 echo inside

icmp permit host 192.168.1.20 echo inside

icmp permit host 192.168.1.40 echo inside

icmp permit host 192.168.1.100 echo inside

sincerely

Patrick