Dynamic DNS

There is a free dynamic DNS site URL

Their dynamic IP update is almost real time and I would like to start up my dynamic DNS server but I do not know how to do that. Any one give me some hint.

What do you mean by dynamic dns server?

-Mr.K

Well, there was an interesting discussion about various companies providing dynamic dns services here: http://www.bsdforums.org/forums/sho...=&threadid=2880

I don't claim to be an expert on DNS, but I decided to look up the DNS records for dnsexit.com and here are the errors I found:

SOA record - Their RNAME field is incorrect (has an @ sign in it)
Their MX records are dnsexit.com (not FQDN) and www.netdorm.com. Both MX records resolve to the same IP and when reverse mapping the IP address of the MX record to the domain name, I ended up with dhcp024-209-193-244.cinci.rr.com, which means their mail delivery is not going to exactly be reliable.

Incidentally ns1.dnsexit.com resolves to the same IP address as dhcp024-209-193-244.cinci.rr.com. Has anyone heard of running a nameserver via an address assigned by dhcp?

[edit] Also noticed that querying the nameservers themselves doesn't seem to contain any info about ns2 being authoritative for this domain at all. freebsd, would you like to post your 2 cents here![/edit]

If you read the dynamic DNS services rating at bsdforums.org I'd give dnsexit.com a big 2 points. So what have they or he (Jack Chen) done wrong?

1) This clueless Jack hasn't added ns2.dnsexit.com to his own DNS server as the slave nameserver but ns2.dnsexit.com is being listed at root.

2) Like you said, bad RNAME format. The @ character should be replaced by a dot.

3) His domain has two MX but both of them point to the same IP and the lower preference one -> www.netdorm.com is a CNAME, which is a serious RFC violation.

4) If you lookup netdorm.com it resolves to the same IP as dnsexit.com, however, ns1.easydns.com is authoritative for netdorm.com. So I don't think Jack should run a DNS server in the first place, not to mention hosting dynamic DNS for his friends or anyone in public.

5) His IP 24.209.193.244 is being listed on multiple RBL lists because of direct spamming with a subject Host www.yourdomain.com at home?. If you care just read here.
Jack also doesn't know how to become a smart spammer.

In the end I would say Jack, with his cheap infrastructure and poor technical skills, doesn't even qualify to run a DNS server in the first place.

>> This clueless Jack hasn't added ns2.dnsexit.com to his own DNS server as the slave nameserver but ns2.dnsexit.com is being listed at root
Yep, that's what I meant when I said "Also noticed that querying the nameservers themselves doesn't seem to contain any info about ns2 being authoritative for this domain at all". I saw ns1 and ns2 listed at root, but when I queried ns1 and ns2 themselves directly with dnsq, I saw no mention of ns2 in the replies. Guess I didn't quite word that correctly though .

I didn't know about him being on the spamhaus list. Looks like he hasn't been running for too long .


Hqpgyjc:>> Their dynamic IP update is almost real time and I would like to start up my dynamic DNS server but I do not know how to do that. Any one give me some hint.

Most dynamic DNS service providers (and this one is no exception) require you to download a client program that you should run on your server. This client program monitors the IP address for your server and if/when it changes, the program notifies the nameservers about the change so that they can update themselves.

You should check out freebsd's ratings for different dynamic dns service providers in the discussion link posted above and see the pros and cons of the different providers (as well as using dynamic dns services in the first place). As for dnsexit's updates being almost real time, their time-to-live field (at least for dnsexit.com) is larger (20 mins) than some of the other dynamic DNS providers around. What this means is that other providers have dynamic IP update happen in more real time than this outfit does.

I have my web server pointed for more than a year at zoneedit.com free.