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HangTenDesign

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HOST IS DOWN - out of the blue

I was watching TV and my wife was surfing the internet when she said she couldn't get to any more web pages from the internet. I tried connecting to a site on the server and the host name wouldn't resolve. I tried localhost and it won't resolve. The only way I can reach a site on the server is with 127.0.0.1

I can't access anything on the server from any other computers within our network.

Could this be a DNS/BIND issue. Why would it stop working just like that out of the blue?

Can someone help me trouble shoot???
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HangTenDesign

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I tried nslookup on the server and it returns the correct information. However, when I try to ping that informaiton I get an "unknown host" return.

Is there some kind of routing problem??? What could this be??? help
>I can't access anything on the server from any other computers within our network.
What kind of machine OS do you have?
Solaris, RedHat Linux or ....
What's the output of
uname -a
ifconfig -a   (as root)
netstat -rn

And also check /var/log/messages (or /var/adm/messages) for error messages.

Wesly
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wesly_chen
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wesly_chen,

FREE BSD on MAC OS X

----> OK, so all I did was shut down DNS/BIND and then restart and it did the trick.

Why would a shutdown and restart fix it??? I have found UNIX to be incredibly stable and mostly cause and effect. What could cause it to do such a thing?
> all I did was shut down DNS/BIND and then restart and it did the trick
Well, for MacOS X, you shouldn't need to run BIND (DNS server). I guess some sort of DNS temporary cache
database corrupted cause the problem.

I would recommend that turn off BIND if you don't need it.
Besides, turn off unnecessary services for security.
MacOS X, by default, will start a lot of services (similar to M$ Windows) which you probably won't use them all the time.

Anyway, glad to know your problem resolved so quickly.
 
Yes, thankyou.

BTW, I am running BIND cause I am running my own DNS server, web, mail, database, with over a dozen domains. I couldn't believe how incredibly powerful MacOS X was under the hood. I am not even using their Server software. It's all there!

Thanks again
That's Unix's world. M$ charge every piece they can charge out of users.......
Check if your DNS server is caching negative replies, and whether you have listed the upstream (ISP) DNS server by name or IP address.

If the ISP has a problem for even a brief interval and you specify upstream by name, your DNS server may cache the fact that the ISP's DNS server is unavailable.  Once that happens, until the cache expires, every query for ns.isp.com gets 'not found'.

Restarting bind clears the cache.


-----Burton