Re: Fixed ip(pc)--->(e1)2600(e0)-dhcp-->asa5505

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Good Morning Team,

Sorry this may bore lots of you, but it is a headache for me trying to learn.

As you see above Fixed ip(pc)--->(e1)2600(e0)-dhcp-->asa5505

From within the router via con port, I can ping both directions
eg: ping 192.168.2.2 = PC
ping 192.168.1.1 = asa5505 gateway

But pinging from the PC direct to the firewall dont work, or to the outside world

Below is my listing if anyone can help it would be great

Thanks from Alan

!
version 12.3
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Router
!
boot-start-marker
boot system flash:c2600-i-mz.123-19a.bin
boot-end-marker
!
!
memory-size iomem 10
no aaa new-model
ip subnet-zero
ip cef
!
!
ip dhcp excluded-address 192.168.1.1 192.168.1.40
!
ip dhcp pool locallan
import all
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
dns-server 212.23.3.100 212.23.6.100
!
!
!
!
!
interface Ethernet0/0
ip address dhcp
ip nat outside
full-duplex
!
interface Serial0/0
no ip address
shutdown
!
interface Ethernet0/1
ip address 192.168.2.1 255.255.255.0
ip nat inside
full-duplex
!
ip nat inside source list 101 interface Ethernet0/0 overload
ip http server
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.1.1
!
!
access-list 101 permit ip 192.168.2.0 0.0.0.255 any log
!
line con 0
line aux 0
line vty 0 4
login
!
!
end

57 Replies 57

stewartrose wrote:

Hi Jon,

If I go into the router via the console, and ping google.com it comes back and says Translating "google.com" ...domain server

% Unrecognized host or address, or protocol not running..

All the best from Alan

Alan

This is because the router is no longer getting a DHCP address from the ASA together with DNS servers so it can't do DNS lookups. This isn't a problem once it's all working as normally routers don't access web pages.

What we will have to do is tell your 192.168.2.x PC what DNS servers to use, hence the reason at the moment i asked you to test with an IP address.

We can setup a DHCP pool for 192.168.2.x on your router when we get internet access working for IP addresses if you want. Note the DHCP pool we deleted was for 192.168.1.x and not 192.168.2.x so we are not just putting back what we deleted

Jon

stewartrose wrote:

Hi Jon,

I can ping 192.168.1.1 now all the time, but no further..

All the best from Alan

Alan

Making progress

On your ASA I have just noticed you have an access-list outside_in but you haven't applied it to the outside interface ie.

ASA(config)# access-group outside_in in interface outside

Also when you ping make sure you ping something beyond the ASA and by IP not DNS name to start with. If you try to ping the outside IP of the ASA it won't work so try the next-hop from the ASA ie. the ISP router.

Also couple of other things -

1) can you edit your previous posts and where you have public IPs just leave the last octet ie. x.x.x.82 for your outside IP on the ASA and also the default-route on the ASA - best to keep those sort of things out of posts.

2) your access-list on the ASA is wide open so is this just a temporary acl to test with ?

Jon

Cisco are currently donating money to the Haiti earthquake appeal for every rating so please consider rating all helpful posts.

Hi Jon,

I add the line on the ASA Mmmm dont like an open firewall

Ok I pinged an IP in Canada should be far enough away

and that was within the router it self, then did it for the PC and stiill nothing...

All the best from Alan

Alan

Can you post "sh running-config xlate" or "sh xlate" from the ASA after you ping ?

Can you try pinging the ISP next-hop from the ASA ?

Jon

Hi Jon, this is getting interesting well for me it is..

All the best from Alan

18 in use, 956 most used
PAT Global x.x.x.82(15) Local 192.168.1.2 ICMP id 4792
PAT Global x.x.x.82(4512) Local 192.168.1.3(1026)
PAT Global x.x.x.82(14435) Local 192.168.1.3(3305)
PAT Global x.x.x.82(4511) Local 192.168.1.3(63826)
PAT Global x.x.x.82(14433) Local 192.168.1.3(3302)
PAT Global x.x.x.82(4510) Local 192.168.1.3(63591)
PAT Global x.x.x.82(14431) Local 192.168.1.3(3300)
PAT Global x.x.x.82(14430) Local 192.168.1.3(3298)
PAT Global x.x.x.82(14425) Local 192.168.1.3(3292)
PAT Global x.x.x.82(14424) Local 192.168.1.3(3291)
PAT Global x.x.x.82(14387) Local 192.168.1.3(3231)
PAT Global x.x.x.82(14050) Local 192.168.1.3(2643)
PAT Global x.x.x.82(14048) Local 192.168.1.3(2641)
PAT Global x.x.x.82(14047) Local 192.168.1.3(2640)
PAT Global x.x.x.82(4470) Local 192.168.1.3(21403)
PAT Global x.x.x.82(13731) Local 192.168.1.3(2051)
PAT Global x.x.x.82(11812) Local 192.168.1.3(3201)
PAT Global x.x.x.82(10305) Local 192.168.1.3(4527)
I remembered

Alan

Can you ping the address in Canada from the actual firewall itself - you may have to temporarily add this to your firewall -

icmp permit any outside

Jon

Hi Jon,

That ip was useless, looks like it does not except so I tried an other one, and have success from every where

well done so far...

All the best from Alan

stewartrose wrote:

Hi Jon,

That ip was useless, looks like it does not except so I tried an other one, and have success from every where

well done so far...

All the best from Alan

So what else do we need to sort out ?

Jon

Hi Jon,

MM...can we do it so I can get to a website url is that possible please... then fix my security HOLE you found

All the best from Alan

stewartrose wrote:

Hi Jon,

MM...can we do it so I can get to a website url is that possible please... then fix my security HOLE you found

All the best from Alan

From PC2 ?

Well you can either manually add the DNS servers (the ones configured under the DHCP pool on the ASA) or you can add a DHCP pool for 192.168.2.x network to the router with the same DNS servers as on the ASA. If you have many clients then probably best to setup DHCP pool on the router.

As for the firewall if you just want web access then remove the access-list from the interface ie.

ASA(config)# no access-group outside_in in interface

you don't need an acl to allow return traffic back in for stateful traffic such as http which is why you could access this forum even without the access-list applied. We only applied it for ping.

If you want ping access then rather than use an acl turn on ICMP inspection on the ASA firewall and then you won't need an acl on the outside. You will only need an acl on the outside interface if you start hosting servers that you want internet users to be able to access.

Jon

Hi Jon,

I thank you very much, you put a lot of time into this and I am very happy, I have learnt a great deal of information, and looking at the views on this forum I think a few more people have gained some insite to....

Thank again Jon

All the best from Alan

Alan

No problem, glad to have helped.

Jon

Cisco are currently donating money to the Haiti earthquake appeal for every rating so please consider rating all helpful posts.

Good Morning Jon,

Sorry I am in trouble on the last part, cannot seem to get the browser to work with domain names...

"Well you can either manually add the DNS servers (the ones configured under the DHCP pool on the ASA) or you can add a DHCP pool for 192.168.2.x network to the router with the same DNS servers as on the ASA. If you have many clients then probably best to setup DHCP pool on the router."

Could I have the code for both methods please Jon.

All the best from Alan

stewartrose wrote:

Good Morning Jon,

Sorry I am in trouble on the last part, cannot seem to get the browser to work with domain names...

Could I have the code for both methods please Jon.

All the best from Alan

Alan

Your ASA is handing out these DNS servers - 212.23.3.100 212.23.6.100

To add manually you go into the networking properties on the PC ie. where you set a static IP you can also specific DNS servers.

To do it via DHCP from the router -

ip dhcp excluded-address 192.168.2.1 192.168.1.10 <-- note you can exclude any IPs from the pool that you want to here
!
ip dhcp pool locallan
import all
network 192.168.2.0 255.255.255.0
default-router 192.168.2.1
dns-server 212.23.3.100 212.23.6.100
!

Jon

If this works can you mark the post as solved as this helps others when searching for answers.

Good Morning Jon,

Thank you for getting back to me, and I understand a ot more now, but do I need to change FastEthernet0/1 port to dhcp for the second option.

All the best from Alan

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