04-08-2010 03:39 AM - edited 02-21-2020 03:55 AM
I have configured a static NAT through my ASA, which for some
reason does not work - I believe the problem is with the NAT or
der rather than the rule itself but I would be most grateful if someone
could assist me in diagnosing the problem.
from command line the rule is ::-
static (UKSCMGMT,management) 10.20.20.20 192.168.1.2 netmask 255.255.255.255
my theory is that anything with a destination address of 10.20.20.20 would be seen as 192.168.1.2 on teh UKSCMGMT interface.
looking at ASDM the rule looks like this
Type Source Destination interface trans address
Static 192.168.1.2 blank management 10.20.20.20
there are some EXEMPT rules relating to 192.168.1.2 - but they are host to host and should not affect the static translation.
Solved! Go to Solution.
04-19-2010 04:48 AM
Yes, absolutely correct. You can configure NAT exemption per network instead of per each host. If you have hosts which can be grouped into a subnet, configure it as network statements instead.
04-08-2010 03:42 AM
Please share the following configuration:
sh run interface --> would like to see the security level
sh run static --> depending on the security level above, need to check the current static statement
sh run nat --> also need to check if the NAT exemption overlaps.
04-08-2010 05:09 AM
both interfaces have a security level of 100
the show run static command gives the following =
static (UKSCMGMT,management) LS-NAT-P-NAG02 ls-mpd-p-nag02 netmask 255.255.255.255
I have now removed all the Exempt statements and ticked the "Enable traffic through the firewall without translation" box
attached is a packet trace of the rule
Thanks you for taking the time to look at this problem.
04-08-2010 05:12 AM
If they are the same security level, you would need to add the following:
same-security-traffic permit inter-interface
04-08-2010 05:34 AM
I have already apllied this command - but I still see the same error ?
thanks
04-08-2010 10:33 PM
Is your goal to perform NAT for communication between the 2 networks that has the same security level? Also, if you don't mind posting your config that would help. Thanks.
04-19-2010 02:35 AM
Hi - I am unable to post the configuration - but would you be able to clarify the use of the checkbox
"Enable traffice throught the firewall without address translation" -
If I check this box. Does that mean I no longer need to specifiy any network exemption
, and only configure the real NATted addresses? Can I safely configure "no nat-control" and remove all EXEMPT configuration ?
many thanks
Keith
04-19-2010 03:13 AM
The "no nat-control" will only work if you have no NAT statement at all configured (including the dynamic NAT). As soon as you have 1 NAT statement, the "no nat-control" will not take effect anymore, and you will still need to configure NAT exemption.
04-19-2010 04:40 AM
many thanks fior the reply.
So that means that even though I have only
a few NAT statements (probably 15 or 20) I will have to configure every single
EXEMPT host or network that exists - of which there are hundreds ?
I have already configured the firewall this way but I was looking for way to tidy up the enormous amount of exempt rules.
regards
Keith
04-19-2010 04:48 AM
Yes, absolutely correct. You can configure NAT exemption per network instead of per each host. If you have hosts which can be grouped into a subnet, configure it as network statements instead.
04-19-2010 05:32 AM
Many thanks for your patience and assistance with this problem.
I have already configured network objects where possible but unfortunately some are hosts.
regards
Keith
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