07-07-2007 08:41 AM - edited 03-05-2019 05:10 PM
Hi, I am a new user and am studying for my CCNA at this time. I have two routers, bought from e-bay. 1 - 2505 and 1 - 2507.
My configuration is this;
2505:
Ethernet 0 - 172.16.0.99 255.255.0.0
Serial 0 - 192.168.1.3 255.255.255.0
Systems connected on the 172.16 subnet to the hub ports
2507:
Ethernet 0 - 10.0.0.2 255.0.0.0
Serial 1 - 192.168.1.1 255.255.255.0
Systems on the 10. subnet connected to hub ports
Now, I can ping all 172.16 hosts from 2505. I can also ping all 10. hosts from 2505 and clients on that host.
From 2507, I can ping 172.16.0.99 on 2505 which is the ethernet 0 interface but I cannot ping anything beyond that.
I have tried RIP, EIGRP and static routes but I cannot route beyond the 2505 router for some reason.
Am I missing something simple here?
Thanks
Gerry
07-07-2007 08:48 AM
Gerry,
What's the default gateway set to for the hosts on the 172.16 network. Their gateway should be set to 172.16.0.99 and make sure the subnet mask is set to /16 bits.
HTH
Sundar
07-07-2007 09:19 AM
Subnet mask is set at 16 bits as indicated by the 255.255.0.0 SN shown in the post.
My routing problem is going in the opposite direction to what you are thinking. The hosts on the 172.16 subnet can successfully ping the hosts on the 10. subnet.
The hosts on the 10. subnet cannot ping anything on the 172.16 subnet.
The hosts on the 10. subnet have their default gateway set to 10.0.0.1 which is the IP address of Ethernet 0 on that router.
Also, they can ping 172.16.0.99 but nothing beyond that. It's like the router is not routing anything. Although the router itself can ping hosts on the 172.16 subnet, it just won't let the other router reach hosts on the 172.16 subnet.
When I ping from the 10. router, I get the ..... and from any host on the 10. subnet, I don't get Destination Unreachable, I simply get Request timed out.
Thanks
07-07-2007 09:26 AM
In your original post you said the IP of E0 on 2507 is 10.0.0.2 whereas the last posting you said the hosts are configured with a gateway address of 10.0.0.1 which one is correct?
If you are still having problems can you post the full sanititized configuration of both routers
07-07-2007 11:28 AM
Sorry, my OP was wrong. E0 on 2507 is 10.0.0.1.
How best would you like the config posted?
Thanks
Gerry
07-07-2007 12:16 PM
Remove any passwords and post the entire configuration.
It's a little odd that you are able to ping the 10. hosts from 172.16 net but not the other way around. Given the fact you are able to ping the gateway address 172.16.0.99 but nothing beyond it from the 2507 and the 10. net the first thing to comes my mind is a possible incorrect gateway setting for the hosts but you have confirmed it's set to the correct address of 172.16.0.99.
Can you make sure another host on the 172.16 network isn't duplicating gateway's address of 172.16.0.99.
HTH
Sundar
07-07-2007 12:47 PM
I had my IP's backwards for the serial interfaces in my OP as well but that shouldn't make a difference as they routers can see each other.
Here is the running-config for both routers;
2507 Config
Current configuration : 1339 bytes
!
version 12.1
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname xxx
!
enable password
!
!
!
!
!
ip subnet-zero
!
!
!
!
hub ether 0 1
link-test
auto-polarity
!
hub ether 0 2
link-test
auto-polarity
!
hub ether 0 3
link-test
auto-polarity
!
hub ether 0 4
link-test
auto-polarity
!
hub ether 0 5
link-test
auto-polarity
!
hub ether 0 6
link-test
auto-polarity
!
hub ether 0 7
link-test
auto-polarity
!
hub ether 0 8
link-test
auto-polarity
!
hub ether 0 9
link-test
auto-polarity
!
hub ether 0 10
link-test
auto-polarity
!
hub ether 0 11
link-test
auto-polarity
!
hub ether 0 12
link-test
auto-polarity
!
hub ether 0 13
link-test
auto-polarity
!
hub ether 0 14
link-test
auto-polarity
!
hub ether 0 15
link-test
auto-polarity
!
hub ether 0 16
link-test
auto-polarity
!
interface Ethernet0
ip address 10.0.0.1 255.0.0.0
!
interface Serial0
ip address 192.168.1.3 255.255.255.0
!
interface Serial1
no ip address
shutdown
!
router eigrp 2
network 10.0.0.0
network 192.168.1.0
auto-summary
no eigrp log-neighbor-changes
!
router rip
network 10.0.0.0
network 192.168.1.0
!
no ip classless
no ip http server
!
!
line con 0
line aux 0
line vty 0
password
login
line vty 1 4
login
!
end
2505 Config
Current configuration : 1128 bytes
!
version 12.1
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Rascals2505
!
enable secret xxx
enable password
!
!
!
!
!
ip subnet-zero
!
!
!
!
hub ether 0 1
link-test
auto-polarity
!
hub ether 0 2
link-test
auto-polarity
!
hub ether 0 3
link-test
auto-polarity
!
hub ether 0 4
link-test
auto-polarity
!
hub ether 0 5
link-test
auto-polarity
!
hub ether 0 6
link-test
auto-polarity
!
hub ether 0 7
link-test
auto-polarity
!
hub ether 0 8
link-test
auto-polarity
!
interface Ethernet0
ip address 172.16.0.99 255.255.0.0
!
interface Serial0
no ip address
loopback
shutdown
!
interface Serial1
ip address 192.168.1.1 255.255.255.0
clockrate 125000
!
router eigrp 1
network 172.16.0.0
network 192.168.1.0
auto-summary
no eigrp log-neighbor-changes
!
router rip
network 172.16.0.0
network 192.168.1.0
!
ip classless
ip http server
!
dialer-list 1 protocol ip permit
dialer-list 1 protocol ipx permit
!
line con 0
line aux 0
line vty 0 4
password
login
!
end
07-07-2007 02:19 PM
There isn't anything configuration that should be causing the problem you are experiencing. Can you configure the following two ACLs and apply it on e0 of 2505. Then initiate a ping from the 10. net to a host on the 172.16 net. Get the output of 'show ip access-list' and let us see whether we are seeing matches on the ACLs. This could help us isolate the problem.
access-list 100 permit ip 10.0.0.0 0.255.255.255 172.16.0.0 0.0.255.255
access-list 100 permit ip any any
access-list 101 permit ip 172.16.0.0 0.0.255.255 10.0.0.0 0.255.255.255
access-list 101 permit ip any any
int e0
ip access-group 100 out
ip access-group 101 in
07-07-2007 03:40 PM
So, now you understand my puzzled presence. :-)
Initially, when I bought these routers off e-bay, they had access lists and configurations already. I completely erased the configurations so that I was starting with a clean config. As a matter of fact, the 2507 came with a password I had to reset and an older versions of the IOS. So, once I had the 2505 at a clean config, I made a backup of the IOS and then installed that on the 2507.
So, there were no acls blocking or allowing anything during my configurations.
I have applied these acls now and there is no difference. Here is the output of the show ip access-list;
Rascals2505>show ip access-list
Extended IP access list 100
permit ip 10.0.0.0 0.255.255.255 172.16.0.0 0.0.255.255 (4 matches)
Extended IP access list 101
permit ip 172.16.0.0 0.0.255.255 10.0.0.0 0.255.255.255
permit ip any any (2417 matches)
Rascals2505>
07-07-2007 04:17 PM
Ok, so to add to the strangeness, it is now working. I am able to ping 172.16 hosts from 10. hosts.
I have to say that I have never been this confused in my life.
I understand IP addressing, routing and subnetting quite well and could not understand why this wasn't working. Being new to Cisco routers, I wondered if it was something I was missing on the platform.
At any rate, I am routing now for whatever unknown reason.
Thanks for your help along the way and the sanity check.
07-07-2007 05:43 PM
These types of unexplainable behavior is what keeps this field interesting :-)
Anyway,the previous posting shows access list 100 with packets leaving the 2505 but access list 101 doesn't show any ICMP echo replies from the hosts on the 172.16 net coming back into the router. This indicates the problem is on the LAN beyond the 2505 and may be on the hosts themselves. The only way to know for sure why it wasn't working is to do a sniffer capture when the problem is happening.
Well anyway glad to hear it's working now!!
Let us know if the problem resurfaces again we shall get to the bottom of the problem.
HTH
Sundar
07-07-2007 06:07 PM
I love a challenge too. What I hate is when you look at something that you know in all your experience should work, but doesn't. It definitely keeps it interesting and that's what I love about it. :-)
Now, I just need to figure out how to get those on the 10. network to access the Internet over that router connection. I may be pushing it here.
I have one of hub ports from 2505 plugged into a 2924XL switch which is connected to a Linksys router connected to my DSL modem.
Is that a requirement for using static routes? Is there a way to assign a default gateway to e0?
Thanks
Gerry
07-07-2007 07:48 PM
Add a default route to the 2505 to point to the Linksys router LAN interface address (gateway). Configure 2505 to NAT the 10. network to 172.16 address. Linksys would then NAT (PAT) 172.16 net using the public IP assigned by your ISP for Internet bound traffic.
HTH
Sundar
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