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Routing issues on ASA 5525X running version 8.6(1)2

Hello ,

I am migration from PIX 515E to ASA 5525X  running version 8.6(1)2 .

The company uses pix as its Internet GW to the ISP ,behind the PIX there's a Cisco 3845 (C3845-ADVENTERPRISEK9-M), Version 12.4(24)T1, RELEASE SOFTWARE (fc3) 

Both devices are running NAT and PAT .

PIX 515
WAN ip   41.x.x.x
LAN ip
gw ip  41.x.x.x

Cisco 3845
WAN ip
Gig 0/0.1  158.29.x.x
GIG 0/0.2
gw ip

Mail server 158.29.x.x

With the current setup they working ok and the pix can route to the the 158.29.X.X  and forward smtp traffic to the mail server .

now my issue is the ASA cant route to 158.29.X.X  addresses internally . I have route inside /24 and I can reach all the devices with 172 series ip  .if I add route inside 158.29.X.X /24  or  /16 their whole class ..I cant cant even ping the 158 ip on the router interface  .I tried running eigrp btwn the router and ASA and had same issues with 158 series .

What could be the problem or what am I missing thanks a lot in advance


Routing issues on ASA 5525X running version 8.6(1)2

Hello Jeremiah,

Routing speaking should be the same behavior,

Is there a way that you could provide us the configuration from both devices this because I will need to see the Ip addresses, route statements and NAT configuration

Also the show route from both boxes ,

Check my blog at for further information.


Julio Carvajal Segura

Julio Carvajal
Senior Network Security and Core Specialist
Community Member

Re: Routing issues on ASA 5525X running version 8.6(1)2

Hi  Julio  ,thanks for your reply please find attached the configs from the old PIX that we are trying to migrate to the ASA , new ASA config , the router behind the PIX config and  IP routes results



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