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takoateli
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RB750 - Can't access internet but I can ping the modem.

Wed Mar 03, 2010 1:15 am

I have an RB750 which I'm trying to install. It's not my first. The modem is not acting as a DHCP server so I have to config the WAN port (Eth1 Gateway) manually. When I've configured the modem (using NAT) I can't access or ping the internet. I can ping the modem. So pings get to the modem but not ip address of servers I know on the internet. Anyone have any idea what this could be? I even downloaded a config from a working RB750 I have at another location, edited the config so it was no longer using DHCP on Eth1, manually configured Eth1, and nothing. Again I can ping the modem but nothing beyond it.

Thanks in advance.

Greg
 
willtech
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Re: RB750 - Can't access internet but I can ping the modem.

Wed Mar 03, 2010 1:30 am

It sounds like you may not have a default route created. You may want to take a look at your routes to make sure that you do have a route created to the outside world from your router. Where are you able to ping the modem from? Is it from the router (Telnet or winbox) or from a PC connected to one of the other ports?
 
takoateli
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Re: RB750 - Can't access internet but I can ping the modem.

Wed Mar 03, 2010 2:15 am

Thanks so much! I am able to ping the modem from an attached computer.

From Winbox I can't ping a known internet IP address.

One thing I accidentally did is I reverse polaritied the unit with a 7 volt power supply someone handed to me when I asked for the unit's power supply.

Greg
 
willtech
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Re: RB750 - Can't access internet but I can ping the modem.

Wed Mar 03, 2010 3:12 am

Could you post your IP routes so everyone can take a look at it? You may also want to tell us what port you have connected to your PC and the WAN.
 
takoateli
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Re: RB750 - Can't access internet but I can ping the modem.

Wed Mar 03, 2010 3:40 am

Thanks. The problem is definitely connected with routes. Thanks for pointing me there. I have another router (x86) set up here and I took a look at the routes there and I could see what was missing. It was the route with a destination address of 0.0.0.0/0 and a gateway of 201.222.12.53 (the modem) with a distance of 1, scope of 30 and target scope of 10. With that one static route in it populates other dynamic discovered routes and it all works.

But there's a complication too and that is if I reset the RB750 and then configure it and get the routes right it works as I said above. But if I take a more complicated setup I had configured and backed up and load that and then set everything right (including the routes) it still won't work! The backup was made under 4.3 and the unit is now running 4.5. I don't know if that could be it. Anyway, it seems like I can make it work, I just have to go through all the trouble of configuring it all again.

What a pain there's no way to take an x86 config and load it on an RB750.


Greg

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