(help) cant ping external web address

Hi guys,

Was hopeing you could help me out with my little lab at home.

I have 5 routers all cabled up through the serial interfaces apart from 1 thats linked up to my home wireless router,which is connected by the ethernet interface.

I can ping an external web address from the router thats connected directly to my wireless router but not from any of the other routers or pc's that are connected to the ethernet interfaces.

I can however ping anyother pc or router on my network including my wireless isp one

I am using rip with a network address of 192.168.10.0/27 and have set up a static route to the isp router

dns works fine on everything and have enable ip http server ,i just cant seem to get outside the local network apart from on the one router directly conncted to the wireless isp router.

Have i missed something stupid here?

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Comments

JavonR

Which device on your network is performing NAT? Sounds like you may not have it turned on if only your first router (with the wan link) can get out.

tech-airman

shaunebop,

shaunebop wrote:

Hi guys,

Was hopeing you could help me out with my little lab at home.

I have 5 routers all cabled up through the serial interfaces apart from 1 thats linked up to my home wireless router,which is connected by the ethernet interface.

Does your "...home wireless router..." support RIPv2 routing?

shaunebop wrote:

I can ping an external web address from the router thats connected directly to my wireless router but not from any of the other routers or pc's that are connected to the ethernet interfaces.

I can however ping anyother pc or router on my network including my wireless isp one

I am using rip with a network address of 192.168.10.0/27 and have set up a static route to the isp router

Have you configured RIP to be version 2?

shaunebop wrote:

dns works fine on everything and have enable ip http server ,i just cant seem to get outside the local network apart from on the one router directly conncted to the wireless isp router.

Have i missed something stupid here?

shaunebop

Yes it does support rip v2 ,but i thought that rip v1 could be used in this configuration as there all under the same subnet mask,allthough they are in different subnets? could this be where i have gone wrong ?

cheers,Shaun

tech-airman

shaunebop wrote:

Yes it does support rip v2 ,but i thought that rip v1 could be used in this configuration as there all under the same subnet mask,allthough they are in different subnets? could this be where i have gone wrong ?

cheers,Shaun

shaunebop,

Since RIP v1 does NOT send subnet masks in their routing updates, if a remote RIP v1 router received a network of 192.168.10.0/27, then it's going to be treated and assumed to be the 192.168.10.0/24 network which means any subnetting done in the fourth octet will be ignored.

shaunebop

tech-airman

Thanks for your reply,i redone the lab but this time with rip v2 so that the subnet mask would be advertised but am still having the same problem.

can ping a web address from router directly connected to the isp router but cant from any of my other routers that are connected back to back by there serial interfaces.

Could this be because i have the routers connected by serial(wan) connections or do you think i could be missing some simple command .

I should probably also mention that the isp router has nat running on it.

Would it help if i posted some running configs?

Thank's for your help,Shaun

remyforbes777

Can you post the config of one of the routers that can't get out. Is there a default route set up on all the other routers?

shaunebop

Ok guys,here are the running configs,the first one servers is the one that i cant get out to the web on and the second config (shipping) is the one directly connected to my isp's wireless router.

Thanks for all your help.

version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname servers
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$g1ly$QxA/DbWZsKg9aAUvErFpH0
!
no aaa new-model
ip subnet-zero
ip name-server 192.168.10.194
ip dhcp excluded-address 192.168.10.65
!
ip dhcp pool servers
network 192.168.10.64 255.255.255.224
default-router 192.168.10.65
dns-server 192.168.10.194
netbios-name-server 192.168.10.194
!
!
!
!
interface Ethernet0
description link to servers
ip address 192.168.10.65 255.255.255.224
!
interface Serial0
description link to shipping
ip address 192.168.10.161 255.255.255.224
clock rate 500000
no fair-queue
!
interface Serial1
description link finance department
ip address 192.168.10.130 255.255.255.224
!
router rip
version 2
network 192.168.10.0
!
ip http server
ip classless
ip route 0.0.0.0 0.0.0.0 Serial0
!
!
!
banner motd shipping departments router
!
line con 0
line aux 0
line vty 0 4
password 7 121A0C041104
login
!
end

here is the shipping one

version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname shipping
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$ohzJ$t27y0SZm1/b0t0Pq649mp/
!
no aaa new-model
ip subnet-zero
ip name-server 192.168.10.194
!
!
!
!
interface Ethernet0
description link to isp wireless router
ip address 192.168.10.193 255.255.255.224
!
interface Serial0
description link to servers
ip address 192.168.10.162 255.255.255.224
no fair-queue
!
interface Serial1
no ip address
shutdown
!
router rip
version 2
network 192.168.10.0
!
ip http server
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.10.194
!
!
!
banner motd shipping department router
!
line con 0
exec-timeout 0 0
line aux 0
line vty 0 4
password 7 02050D480809
login
!
end

networker050184

You said you can ping your wireless router form the other routers?

If thats true then you should have reacability to the wireless router.

How is your NAT setup on the wireless router?

Your pings will have a source address of the outgoing interface of the router they originate form so if you have the NAT set up for the subnet of 192.168.10.193 255.255.255.224 only your pings from the other subnets won't get NATed and will fail when attempting to reach the outside.

I would verify for sure that you can ping the inside address of the wireless router (and get a reply) from the others. If you can check the NAT config on the wireless router.

shaunebop

Think you have hit the nail right on the head there networker050184

Is there anyway i can get the other routers on the different subnets past the nat on the wireless router ?

networker050184

I'm not sure. I'm not very familiar with home based wireless routers , but I'm sure if you get in the web gui you could probably figure it out.

What type of wireless router is it?

shaunebop

It's a netgear,which i can get inside so ill have to do some digging around :DThanks for your help much appreciated

tech-airman

shaunebop,

shaunebop wrote:

tech-airman

Thanks for your reply,i redone the lab but this time with rip v2 so that the subnet mask would be advertised but am still having the same problem.

can ping a web address from router directly connected to the isp router but cant from any of my other routers that are connected back to back by there serial interfaces.

Could this be because i have the routers connected by serial(wan) connections or do you think i could be missing some simple command .

On the router connected directly to the wireless router, do you have a static default route configured pointing to the IP address of the wireless router?

shaunebop wrote:

I should probably also mention that the isp router has nat running on it.

Would it help if i posted some running configs?

Thank's for your help,Shaun

networker050184

tech-airman wrote:

shaunebop,

shaunebop wrote:

tech-airman

Thanks for your reply,i redone the lab but this time with rip v2 so that the subnet mask would be advertised but am still having the same problem.

can ping a web address from router directly connected to the isp router but cant from any of my other routers that are connected back to back by there serial interfaces.

Could this be because i have the routers connected by serial(wan) connections or do you think i could be missing some simple command .

On the router connected directly to the wireless router, do you have a static default route configured pointing to the IP address of the wireless router?

shaunebop wrote:

I should probably also mention that the isp router has nat running on it.

Would it help if i posted some running configs?

Thank's for your help,Shaun

Did you not look at his config?

shaunebop wrote:

......ip route 0.0.0.0 0.0.0.0 192.168.10.194 .........

adam-b

shaunebop, where does your wireless router get its outside interface's ip address? Is it from another device in your home such as a dsl or cable modem? If this is the case then i would use one of the cisco routers as your nat device and put your wireless router in another vlan on your internal network. In this way you would only be using your wireless "router" as a wireless access point.

I would takethe eth interface from your cable/dsl modem and connect that to one of your cisco router's eth interfaces and then set that interface to get its ip address via dhcp. I would then set that interface as its default router and then inject that default route into your rip routing. I would also set up nat on that same router to allow translations for all of your internal subnets. You could even use this router as your one and only dhcp server and setup dhcp relay on the other routers.

Of course parts of this setup will not work if your wireless router is the same device that connects to your cable line or dsl. Good luck!