ipsec tunnel established but no pinging

I have a site-to-site vpn tunnel established between a 2600 router and
a Pix501 and both IKE and IPSEC tunnel shows up as established with no
errors. I can ping the endpoint IPs from both sides but we can not ping
each other's internal networks. The endpoint on my 2600 router is a
loopback inteface I created and I added a route so that any traffic
destined for that remote site should go through this interface. I don't
know what the problem is and I can't tell where the ping is failing.
Anyone shed any light on this? Is it the loopback interface that's
having the problem? I already have a vpn tunnel terminating to my
outside interface and want to avoid adding this other one to it as
well...

 

maybe icmp is forbidden troughout pix

psychogenic ha scritto:

 

or, try enabling debug mode and see what happens,

cheers,
Zuhair Al Zubaidi

 

Thanks all. I turned on debugging by doing "debug ip icmp" and I'm just
getting alot of garbage. I don't think it's catching any of the pings I
am sending across. For example I tried pinging a known good network
across a good vpn tunnel and the logs don't show anything at all. Is
there a different command?

Also I'm thinking the issue might be with the remote PIX. I noticed at
their end there are no routes on the routing table. It's a PIX501
running 6.3.5 IOS and I am assuming that a default route to the outside
interface is not assumed automatically by the device. And so if my
pings even do reach the remote machine the echo-reply wouldn't come
back since there is no default route? Does this make any sense?

Thanks.

 

Please show from your config:

NAT Statements
ACL's regarding your crypto map
IPSEC and ISAKMP config

 

I would also assume that if you set your logging level to 7 and sent
traffic across the tunnel your syslog would shoot some messages at you
in regards to no translation for traffic x.x.x.x to y.y.y.y
Where x.x.x.x is your local subnet and y.y.y.y would be the remote subnet?

If so you need to exclude those subnets from performing NAT.

Google for NAT 0 and, also in another reply to this post I listed some
items from your config to post.

HTH

 

Yes, I exlcuded both subnets from NAT. I don't believe its a NAT issue
but I guess strangers things have happened. Here is the config for the
remote PIX:

Local Site Network: 10.1.1.0/24
Remomte Site Network: 20.1.1.0/24

Remote Site PIX:

interface ethernet0 auto
interface ethernet1 100full
nameif ethernet0 outside security0
nameif ethernet1 inside security100
hostname pix
domain-name
clock timezone JST 9
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
object-group service Citrix-Service tcp
port-object eq echo
port-object eq citrix-ica
port-object eq www
port-object eq https
access-list outside_access_in permit icmp any any log 0
access-list outside_access_in permit ip 10.1.1.0 255.255.248.0 20.1.1.0
255.255.255.0
access-list inside_access_in permit icmp any any log 0
access-list inside_access_in permit ip any any
access-list inside_outbound_nat0_acl permit ip 20.1.1.0 255.255.255.0
10.1.1.0 255.255.248.0
access-list outside_cryptomap_20 permit ip 20.1.1.0 255.255.255.0
10.1.1.0 255.255.248.0
access-list outside_inbound_nat0_acl permit ip 10.1.1.0 255.255.248.0
20.1.1.0 255.255.255.0
pager lines 24
logging on
logging timestamp
logging trap informational
logging host inside syslog
icmp permit host syslog outside
icmp permit any outside
icmp permit host syslog inside
icmp permit host RTX-1000 inside
mtu outside 1500
mtu inside 1500
ip address outside pppoe setroute
ip address inside 20.1.1.1 255.255.255.0
ip verify reverse-path interface outside
ip audit info action alarm
ip audit attack action alarm
arp timeout 14400
global (outside) 1 interface
nat (outside) 0 access-list outside_inbound_nat0_acl outside
nat (inside) 0 access-list inside_outbound_nat0_acl
nat (inside) 1 0.0.0.0 0.0.0.0 0 0
access-group outside_access_in in interface outside
access-group inside_access_in in interface inside
timeout xlate 0:05:00
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 sip-disconnect 0:02:00 sip-invite 0:03:00
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
no snmp-server location
no snmp-server contact
snmp-server community public
no snmp-server enable traps
floodguard enable
sysopt connection permit-ipsec
crypto ipsec transform-set ESP-3DES-MD5 esp-3des esp-md5-hmac
crypto map outside_map 20 ipsec-isakmp
crypto map outside_map 20 match address outside_cryptomap_20
crypto map outside_map 20 set peer 192.168.0.150
crypto map outside_map 20 set transform-set ESP-3DES-MD5
crypto map outside_map interface outside
isakmp enable outside
isakmp key ******** address 192.168.0.150 netmask 255.255.255.255
no-xauth no-config-mode
isakmp identity address
isakmp keepalive 10 4
isakmp policy 20 authentication pre-share
isakmp policy 20 encryption 3des
isakmp policy 20 hash md5
isakmp policy 20 group 2
isakmp policy 20 lifetime 86400

 

Just a thought, but how about adding isakmp nat-traversal in the
configs? I know this is the command for the PIX, but not sure about the
router.

Cheers

 

I believe that you do not need the above outside entry in your access-list
as you have permitted

This feature allows your VPN traffic to bypass the access-list on the
outside interface.

I am also unsure why you have this:

access-list outside_inbound_nat0_acl permit ip 10.1.1.0 255.255.248.0
20.1.1.0 255.255.255.0

I have only had a quick look at the config but assuming that you wanted to
exempt this from nat on your remote router, don't you need to do the No NAT
on the router.

So on the PIX you will have:

An access-list permitting traffic from the PIX (LAN) to the remote router
(LAN) - Your Crypto Access-List
A no nat statement for the same

+

On the router you will have:

An access-list permitting traffic from the Router (LAN) to the remote PIX
(LAN) - Your Crypto Access-List
A no nat statement for the same

Could be wrong but maybe someone else could confirm / deny.

HTH.

Regards

Darren

 

These were created from the vpn site to site wizard on both router and
firewall. I'm assuming the outside_access_in rule was created to define
which traffic needs to be encrypted and the other rule to have no NAT
between the two networks. I have the same rules applied on a different
firewall connected to the same router and it works perfectly fine. The
only difference between these two tunnels is that the working one's
endpoint is my outside interface of the local router and the non
working is on a loopback interface i created.

 

It's fixed now. What I did was change the local endpoint to my outside
interface and changed the routes to go there. I don't know why this
doesn't work with a logical interface...