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Hey Guys,
My ISP's DNS severs keep going down over and over. I want to set up a redundant backup so the whole house dosen't lose the Net when this happens. I got the IP's of one of the root severs from ICANN but having the IP entered in as a DNS server in Control Panel makes no difference. I can ping the DNS server and Traceroute to it but it don't work as a backup.....anything else I can do?
Use the dns servers from another ISP. You can use any dns server so pick the largest isp you can find and use theirs.
Some ISPs don't let you use another DNS than their own. It could explain your problem.
But in all case, a lot of DNS have a webpage you can use to make a DNS resolving. So, even if it is not the easiest solution, you can resolve manually via the web each site name.
Could I Install DNS services on my FreeBSD box and then connect to that?
I had the same problem trying to use any of the ?.root-server.net nameservers. I do not believe they reply to queries in a format readable to standard library functions. A proxy nameserver is required to translate the answer into a readable format, I believe. This would make sense as if everyone used the root servers, the load on them would quickly shut down the entire DNS system and the world would plunge into a chaos of biblical proportions. I am currently using microsoft's dns server (really because I never bothered to look for any more) because my ISP gave me the same hassles with name resolution. Its address is 131.107.1.240. Never had any problems with M$'s server. Interestingly enough, I can only perform a ping or traceroute with the IP address. If I plug in the name of a nameserver, I keep getting unknown server errors.
The other option would be to make a VERY large hosts file, possibly downloading it from your ISP when the server is up, and updating it once a week or so. You could also set up your own nameserver, which should be able to communicate with the root servers. Anyways, hope this helps.
The root servers are not "real" DNS servers by my understanding. They are "hint" servers which minimizes the amount of traffic they have to output and the amount of data they need to keep.
It works kinda like this. Under normal circumstances you would ask for www.yahoo.com. You machine thinks "uh oh... He's speaking english again" and sends a request to your DNS server to translate this to an IP. Your DNS server looks in it's cache to see if it already knows the answer. If it does it provides it and your away. If not it consults it's forwarder which may be another ISP's. If it get no valid reply and is allowed to use recursion it questions the root servers. However this is a different request. All the previous requests were "What is the IP address of the host at yahoo.com called www"? This new request is "Got any idea who I should ask for information about yahoo.com"? The answer got on the other requests would have been "Authoritative - 123.123.123.123" meaning that the request had been made to the primary nameserver on the internet for the domain yahoo.com - or - "non-authoritative - 123.123.123.123" meaning that the secondary or another server on the internet with the information in it's cache replied, (and the TTL was still valid). The answer from the root servers is simply "Hint - 123.123.123.111/123.123.123.112" these being the primary and secondary nameservers registered to yahoo.com in the internet. Your DNS server would then make the request for the www host from the primary nameserver for yahoo.com. If that is down, (the default timeout is 2 seconds I believe), it makes the same request to the secondary. If it still gets no reply then you get the DNS error from your browser.
The upshot is that you can't use the root servers to do standard dns lookups - the format of both the question and the answer is different. If you use a Win2k/XP pro box you could use nslookup to find a remote DNS server that will answer you and use it's IP as the secondary. OTOH your ISP should be constantly and loudly slapped for double DNS failures. You pay for the service and it should damned well work. I found that a pointed email copied to your local Better Business Bureau seems to get a really quick response if you don't get rapid satisfaction...... :D