monitoring internet connectivity from the router

[melbert2002]

Hello all,
We are having problems with intermittent connectivity problems through our hosting provider. We have a monitoring solution that will report problems with reaching our router externally and internally from a server in the solution.

What I would like to do is monitor from the router to the internet. Currently when I check the logging it does not show any interuption in service. I think this is because the connection to our service provider is up, but beyond that is the interuption.

What I was wondering is there a way for the router to monitor or show the connectivity errors out to the internet. This might be a really simple way of putting it, but can the router monitor yahoo.com or something and if it cant reach it send the error to the log on the router.

Thanks

mel

 

[zinkann]

Have you ran pings out to the internet? 4.2.2.2? Tracerts? Easiest method.

CCNA, Network+

 

[melbert2002]

hehe, that is my favorite IP to test.

Everytime I get on the router I test it out. The problem is that the connection will go down for 1 min or so, by the time I get the report of the issue, its gone. Im just looking for an automated way of doing this and shove it into the log. This is o I can have something accurate to report rather than relying on the hosting provider to tell me.

Thanks

Mel

 

[t0mm0]

The traceroute will outline where exactly the link is going down or where you're loosing packets.

As it may not be in your SP network, where the issue is?

 

[burtsbees]

What do you mean, the connection will go down for a minute? Does the status on the interface report down/line prot down? That will definitely show in your logs...
You can find internal problems with sh interface...
Extended pings with sweep ranges from a Cisco device are good as well.
Please be more specific as to your exact problem (unless it is that simple), like any particular machine, any particular app (tcp/udp port), any particular site/destination, etc. Traceroute can find black hole routes, but not necessarily interruptions in service.

Burt

 

[melbert2002]

Burt,
thanks for the help there

I think the problem that Im seeing is on is the internet connectivity that Im using from my hosting provider is going down. For example: they will make a config change or update an ACL to their core router and this will bump the connectivity to the internet for some reason (they have told me this as well).

The connections back internally work, and my router can see a physical connection, its just when it tries to go out to the internet there is no connection. I am monitoring the connection to my router from an external source so I know when the connection is down, but internally the connection from my router to theirs is still up. I have initially set up some monitoring from the inside to check an external source, so that will help in determaining the actual time of the loss of internet connectivity.

I was just wondering if there is a way to monitor a web site or an IP from the router its self and if the connectivity goes down will send something to the log.

Thanks

Mel

 

[Minue]

Hello
You could try SLA,I haven't studied this protocol yet.So I can't garantee that it's the solution.

Regards

 

[burtsbees]

Well, it sounds like they admit to it going down when some Cisco code monkey wannabe on their side goofs with an acl.
Are you NATting internally on your edge router, or is the ISP doing this? That's what the problem sounds like it could be. What sort of connection do you have with the ISP?
Enabling syslog logging from a source interface on the router would also work...you can configure the syslog server to send keepalives to any IP address you want, with any frequency you want. I use Kiwi (free).
Just create an RSA key signature, enable logging, tell the router what source interface, and what server to log to, tell it what domain name (can be "local"), and tell it what level or logging you want...

Here's an example...

logging count
logging userinfo
logging buffered 4096 debugging
logging console errors
ip domain name directly_connected.com
logging dmvpn
logging history warnings
logging trap debugging
logging source-interface Dialer0
logging server-arp
logging 10.69.69.2
crypto key generate rsa
It will ask what size keys to generate (512 default, 1024 for ssh ver 1, 2048 for ssh ver 2). Then open Kiwi and minimize it (mine is on the Windows box at 10.69.69.2), and it will log everything that happens on that interface!

Burt

 

[keebe418]

Are you noticing collisions on the router? Or constant up/down status changes on an interface?

I have seen many times where some interface duplexing is incorrectly set for their ISP at half-duplex or auto(which sometimes doesn't set the correct duplexing) and these collisions occur. Check with your ISP what it should be set at.

If it is set at auto or half try changing the interface to full-duplex where collisions cannot occur.

http://www.cisco.com/warp/public/63/eth_collisions.html#topic1

-Shawn