ASA 5520 can't ping Config Problem

pgatt62polly66 · ‎09-22-2010

ASA 5520 Config same-security-level Problem

Hi All

I thought that putting an ip address on the outside interface,the inside secure interfaces, a default route to the outside interface, a couple of NAT statements was all that was needed to get an ASA 5520 working. And that was basically all that was asked.
Like a lot of other stuff that I'm sure you've seen before, more and more requests were added to the original remit to which I thought, OK, I know my way round this to a certain degree and I'm sure that I'll work out something or find a way round it using all the available stuff from Cisco and the web.( I've got a CCNP Switch exam under my belt,working on the rest, and a CCNA Security and Wireless and Field Engineer qualifications, so to a degree consider myself quite knowledgable. So I thought)
Anyway, the more I tried to fix the problem the worse it became. I'm not convinced that its too complicated but the solution is still eluding me.
What I tried to configure was a system with two seperate inside networks for Data and Voice protected by a ASA 5520 which acts as a router and sole access to the outside world for both of these inside networks but also as device that would point to other connected legacy networks attached to a Nortel switch located somewhere deep in the system, which are ear-marked for migration to the ASA 5520 once the Nortel switch has been decommissioned, and some deny statements for email smtp port 25.
After setting up and proving internet access for both inside networks G0/1 and G0/2 it was discoverd that a ping could not ping from either inside network to the other and likewise to the outside G0/0 interface although internet access was still available. I put an icmp inspect command into the global policy but this didn't work so did a kind of Static NAT/ip route fudge that seemed to sort the ping problem out. However when adding commands for VPN tunnels I lost the ping functionality.
This is where after trying to work out a solution for over an hour I started grasping at straws, which may explain some commands in my config that don't make any sense. I just couldn't see where I had went wrong.
Anyway, the customer is content enough with firewall protected internet access but its not sitting well with me professionally that I've not provided them with all that they asked for.
My config now as it stands has probably a few commands that shouldn't be there and undoubtedly some that should, but I fear I'm now a bit out of my depth.
Ignoring the routes to the other networks via the Nortel switch, what I ultimately need and I know this asking a lot, is for someone to take my configuration, correct it and let me see where I've gone wrong. Many thanks

******************************************************************************************************************

:
ASA   Version 8.2(1)
!
hostname ISC-EDI-ASWFW
domain-name   iscinternal.com
enable password DVYtjzRh.k2l3Eyj encrypted
passwd   2KFQnbNIdI.2KYOU encrypted
names
!
interface GigabitEthernet0/0
nameif outside
security-level 0
ip address XX.XX.XX.154 255.255.255.248
!
interface GigabitEthernet0/1
speed 100
duplex full
nameif inside1
security-level 100
ip address 172.24.19.252 255.255.252.0
!
interface GigabitEthernet0/2
speed 100
duplex full
nameif inside2
security-level 100
ip address 172.24.23.254 255.255.252.0
!
interface   GigabitEthernet0/3
shutdown
no nameif
no security-level
no ip address
!
interface Management0/0
nameif management
security-level 100
ip address 192.168.1.1 255.255.255.0
management-only
!
ftp mode passive
dns domain-lookup inside1
dns domain-lookup inside2
dns domain-lookup outside
dns server-group DefaultDNS
name-server 172.24.16.2
name-server 172.24.0.10
name-server XX.XX.XX.6
domain-name iscinternal.com
same-security-traffic permit inter-interface
same-security-traffic permit intra-interface
access-list VPN-NONAT extended permit ip 172.24.16.0 255.255.252.0 192.168.10.0 255.255.255.0
access-list VPN-NONAT extended permit ip 172.24.16.0 255.255.252.0 172.24.8.0 255.255.252.0
access-list VPN-NONAT extended permit ip 172.24.16.0 255.255.252.0 172.24.20.0 255.255.252.0
access-list VPN-NONAT extended permit ip 172.24.20.0 255.255.252.0 172.24.16.0 255.255.252.0
access-list EDI-BRUSS extended permit ip 172.24.16.0 255.255.252.0 172.24.8.0 255.255.252.0
pager lines 24
logging enable
logging timestamp
logging buffer-size 16384
logging monitor notifications
logging trap errors
logging asdm informational
logging host inside1 172.24.16.2
mtu management 1500
mtu inside1 1500
mtu inside2 1500
mtu outside 1500
ip local pool VPN-POOL 192.168.10.1-192.168.10.50 mask 255.255.255.0
no failover
icmp unreachable rate-limit 1 burst-size 1
icmp permit 172.24.20.0 255.255.252.0 inside1
icmp permit 172.24.16.0 255.255.252.0 inside2
no asdm history enable
arp timeout 14400
global (outside) 1 interface
nat (inside1) 0 access-list VPN-NONAT
nat (inside1) 1 0.0.0.0 0.0.0.0
nat (inside2) 0 access-list VPN-NONAT
nat (inside2) 1 0.0.0.0 0.0.0.0
route outside 0.0.0.0 0.0.0.0 XX.XX.XX.153 1
route inside1 172.24.0.0 255.255.252.0 172.24.19.254 1
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout   sip-provisional-media 0:02:00 uauth 0:05:00 absolute
timeout   tcp-proxy-reassembly 0:01:00
dynamic-access-policy-record   DfltAccessPolicy
aaa-server ACCESS-SRVR protocol radius
aaa-server   ACCESS-SRVR (inside1) host 172.24.16.2
key Fountain42!
aaa   authentication serial console ACCESS-SRVR LOCAL
aaa authentication   ssh console ACCESS-SRVR LOCAL
aaa authentication enable console   ACCESS-SRVR LOCAL
http server enable
http 192.168.1.0   255.255.255.0 management
http 172.24.16.0 255.255.252.0 inside1
http   172.24.20.0 255.255.252.0 inside2
http redirect outside 80
no   snmp-server location
no snmp-server contact
snmp-server enable   traps snmp authentication linkup linkdown coldstart
crypto ipsec   transform-set VPN-TRSET esp-3des esp-sha-hmac
crypto ipsec   security-association lifetime seconds 28800
crypto ipsec   security-association lifetime kilobytes 4608000
crypto map EDI-BRUSS   10 match address EDI-BRUSS
crypto map EDI-BRUSS 10 set pfs
crypto   map EDI-BRUSS 10 set peer XX.XX.XX.18
crypto map EDI-BRUSS 10 set   transform-set VPN-TRSET
crypto map EDI-BRUSS 10 set   security-association lifetime seconds 25200
crypto map EDI-BRUSS   interface outside
crypto isakmp identity address
crypto isakmp   enable outside
crypto isakmp policy 10
authentication pre-share
encryption 3des
hash sha
group 2
lifetime 25200
telnet timeout 5
ssh 172.24.16.0 255.255.252.0 inside1
ssh 172.24.20.0 255.255.252.0 inside2
ssh timeout 5
console timeout 0
dhcpd address 192.168.1.2-192.168.1.254 management
dhcpd enable management
!
threat-detection   basic-threat
threat-detection statistics access-list
no   threat-detection statistics tcp-intercept
ntp server 62.206.250.163   source outside
webvpn
enable outside
svc image   disk0:/anyconnect-win-2.4.1012-k9.pkg 1
svc enable
tunnel-group-list enable
group-policy ANYCONNECT-POLICY internal
group-policy   ANYCONNECT-POLICY attributes
dns-server value 172.24.16.2   172.24.0.10
vpn-tunnel-protocol svc webvpn
webvpn
svc   keep-installer installed
svc ask enable default svc timeout 20
username   admin password we1JsUwd6pW4pQ2W encrypted
username dancoop password   NFAr6PJhZEifx4Wo encrypted
username dancoop attributes
service-type remote-access
tunnel-group telecommuters type remote-access
tunnel-group TELECOMMUTERS type remote-access
tunnel-group TELECOMMUTERS general-attributes
address-pool VPN-POOL
default-group-policy ANYCONNECT-POLICY
tunnel-group TELECOMMUTERS webvpn-attributes
group-alias sslgroup-users enable
tunnel-group XX.XX.XX.18 type ipsec-l2l
tunnel-group XX.XX.XX18 ipsec-attributes
pre-shared-key *
!
class-map inspection_default
match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
parameters
message-length maximum 512
policy-map global_policy
class inspection_default
inspect dns preset_dns_map
inspect ftp
inspect h323 h225
inspect   h323 ras
inspect rsh
inspect rtsp
inspect esmtp
   inspect sqlnet
inspect skinny
inspect sunrpc
inspect xdmcp
inspect sip
inspect netbios
inspect tftp
   inspect icmp
!
service-policy global_policy global
prompt hostname context
Cryptochecksum:c410cd0af890f5fb81df2852aea8f4fb
:   end
no asdm history enable

August Ritchie · ‎09-22-2010

Would you mind posting the results of this packet tracer where you input IP addresses on your inside1 and inside2 respectively that you want to ping between?

packet-tracer input inside1 icmp 8 0

pgatt62polly66 · ‎09-23-2010

August

Thanks for the reply. The ASA is on a customer site so I do not have access to it at the moment but I will try your test suggestion out first chance and let you know the results if thats ok.

Regards etc

Magnus Mortensen · ‎09-22-2010

Is the issue that hosts directly connected to the inside1 interface cannot reach hosts that are routed by the nortel (also located off inside1)? From your description it sound like the hosts that are direct connected to inside1 have the default gateway set to be the ASA, no? It sound likw traffic would need to hairpin on the inside1 interface. - magnus

pgatt62polly66 · ‎09-23-2010

Magnus

Yes that is the issue I'm sure. Hairpinning is not something I'm strong on yet and I suppose once the Nortel switch is decommissioned all traffic should ppoint toward the ASA . Yes ?

Anyway. i'm not able to access the ASA as its on a customer site but will pass on your advice and let you know the outcome if thats ok.

Regards etc

pgatt62polly66 · ‎09-24-2010

Hi Magnus

Isn't it true that two inside interfaces with each the same security level setting should be capable of communicating between each other by default, therefore foregoing any further configurations.

Pat

praprama · ‎09-24-2010

Hey Pat,

By default, communication between interfaces with same security level is not allowed. To allow that, you need the command "same-security-traffic permit inter-interface".

Please note that having this command alone doesn't suffice. You will still need to permit traffic if you have ACLs, etc.

Hope this helps!!

Thanks and Regards,

Prapanch

pgatt62polly66 · ‎09-24-2010

Thanks Prapanch,

I've got the relevant commands in my config but they still didn't do the trick.

More food for thought eh?

Cheers all the same

Pat

praprama · ‎09-24-2010

Hey Pat,

I apologize if i am making you re-iterate things here but what all are the problems you are facing now? Please list those out and i will try my best to answer those.

Regards,

Prapanch

pgatt62polly66 · ‎09-24-2010

Prapanch

Thanks pal. I'll get them to you first chanceI get

Cheers

Pat

pgatt62polly66 · ‎09-24-2010

Hi Prapanch

No problem at all

The inside secure networks off of G0/1 and G0/2 can both access the internet but the client wants to be able to ping bteween them for testing purposes and why not. Thinking this should be possible after referring to the 1500 page manual but not getting it to work I put a icmp inspect command into the global policy that you should see near the end of the config. There is also same-security commands in there too.

An earlier suggestion from Magnus was that it could require a hairpin set-up but I'll have to read up on that first.

There was another gateway in the system at the time, the Nortel switch I believe, and I don't know if that's causing an issue. Maybe it is maybe it isn't.

There were other statements that were intended to be placed into the config, namely static routes that should not be routed by the ASA but be sent to the Nortel until further developments. Namely the decommissioning of the Nortel, but I ran out of time. Any help would be great as I know the customer isn't fully satisfied.

If I can at least sort out the ping between both inside networks its a step in the right direction,

Regards Pat

praprama · ‎09-24-2010

Hey Pat,

Issue mostly likely looks to be with the NAT rules. Try adding the below 2 commands and see if it works:

static (inside1,inside2) 172.24.16.0 172.24.16.0 netmask 255.255.252.0

static (inside2,inside1) 172.24.20.0 172.24.20.0 netmask 255.255.252.0

I am guessing that the 2 networks on inside1 and inside2 and 172.24.16.0/22 and 172.24.20.0/22. Hope that's right!

Regards,

Prapanch

pgatt62polly66 · ‎09-24-2010

Prapanch

Thanks I'll try that first chance I get.

How does this command work?

Pat

praprama · ‎09-24-2010

Hey Pat,

In general, we have 2 ways to read a static command in the below format:

static (i/f1,i/f2) a.b.c.d e.f.g.h

1) Source IP address Translation: In this case, we follow the normal NAT order of operation as given in the link below:

http://www.cisco.com/en/US/docs/security/asa/asa80/configuration/guide/cfgnat.html#wp1042696

2) Destination IP address translation: In this case, the firewall uses the destination IP address of the packet, and decides which interface should be the egress interface and how the destination IP address field in the packet has to be translated. Details can be found at the below link:

http://www.cisco.com/en/US/docs/security/asa/asa80/configuration/guide/ip.html#wp1090528

Let's assume a scenario. We have the above static command on an ASA and it receives a packet on the i/f2 interface of the ASA with a destination IP address as a.b.c.d. So, the ASA decides that this packet should be directed out i/f1 interface of the ASA and translates the destination IP address field to e.f.g.h. Please note that the packet still goes through the remaining stages of apcket processing (ACL, Source NATing, service-policy, etc.) but this "static" will be used to decide the egress interface (route-lookup).

Hope this makes things clear!! Let me know if there is something that is unclear!!

Thanks and Regards,

Prapanch