midnite Posted January 4, 2007 Share Posted January 4, 2007 at the most beginning, i would like to find some free dynamic DNS provider apart from no-ip (i still want to !!)and now my friend has just talking about registering a .com account, so i think of the possibility of hosting a .com at my home server with a dynamic IP. He said that domain names' TTL last for more than a day!! It will be totally unacceptable for hosting under a dynamic IP address. Is it true actually? Is there more or less a standard TTL for domain names? Or the TTL is determined by the domain name registration organization or the one we park the domain at? If it is the former, and it serves dynamic DNS services also, its TTL will be quite low as it can set it as low as it can, right? Link to comment Share on other sites More sharing options...
jesh Posted January 4, 2007 Share Posted January 4, 2007 Since I just bought a digital camera, I'm reading "Through the Lens" when I see TTL. Are you referring to "Time to Live"? If so, yeah, it can take up to 36 hours for a changed DNS setting to propagate through the Internet. As far as I know, there is no way to lessen this time. Link to comment Share on other sites More sharing options...
midnite Posted January 4, 2007 Author Share Posted January 4, 2007 haha, that's cool! Through the Lens~~ngng.. to propagate, is sending the information through a DNS server to another, until all have the updated one. Yet, as i know, the TTL is the interval to send out the information of a domain name, and a DNS server have all its domains with all different TTL (am i right?) so, a DNS server will check if any of its holding domains' TTL expire and fetch a new copy of information for them. the question comes to Who determine the TTL? if it is low, let's say 1 minute, it won't be a problem to spread it through the globe within a few minutes. yet if it is too low, it will be a burden for the whole traffic. so i guess there is some rule or some international authority to determine it, the TTL (thro the Lens, LOL). Link to comment Share on other sites More sharing options...
jesh Posted January 4, 2007 Share Posted January 4, 2007 heh. I've been taking pictures like crazy.I don't know the specifics about how DNS settings propagate through the network, but, in my experience, it takes up to 36 hours and there isn't much you can do about it. My guess is because DNS servers (there are thousands) each have their own intervals at which they check other DNS servers for updates and 36 hours is statistically how long it takes for each server's interval to take place. Link to comment Share on other sites More sharing options...
midnite Posted January 4, 2007 Author Share Posted January 4, 2007 oh.. i don't want it to be true, yet it seems to be -.-n, is there any suggestions for free dynamic DNS providers apart from No-IP and dynDNS from those who come across here? Link to comment Share on other sites More sharing options...
justsomeguy Posted January 8, 2007 Share Posted January 8, 2007 I think dnsalias.com is another one. TTL doesn't really apply to dynamic DNS, because usually the DNS server will be the server at the dynamic DNS host. That address will never change, it will always be their server. They just need to make sure that whenever they get asked what the IP for a certain domain is that they have the current IP, but it doesn't necessarily need to get propagated all around the net. Other DNS servers just need to know that in order to reach the IP of your domain, they need to look it up at the dynamic DNS server, and that server is the only one that needs your current IP. Link to comment Share on other sites More sharing options...
midnite Posted January 10, 2007 Author Share Posted January 10, 2007 thanks very much for a detailed reply from justsomeguy.Do u mean that if i park a domain in a dymanic DNS company (let's say company A), the IP of my domain at all the others DNS server will just be the IP of company A? and whenever my domain is requested for an address resolution, the clients will be given the IP of company A. when my clients reach company A, company A will redirect them to my IP?i know none for really parking a www.my_name.com domain in them as i didnt try any. Yet in my experience of using their free plans, having a my_name.dnsalias.com. if i ping it, it does return *MY IP*. Does it mean that if i park a www.my_name.com domain in them, and my IP will also be returned, although company A's IP is storing in all the other DNS servers ?? Link to comment Share on other sites More sharing options...
justsomeguy Posted January 10, 2007 Share Posted January 10, 2007 That's close, but not quite. They don't go to company A's IP, they go to company A's DNS server. Here is a real-world example. Click on this link to do a DNS lookup for ans.dnsalias.com:http://www.dnsstuff.com/tools/lookup.ch?na...om&type=ALLNotice the top few lines: How I am searching:Searching for ans.dnsalias.com ALL record at m.root-servers.net [202.12.27.33]: Got referral to D.GTLD-SERVERS.NET. (zone: com.) [took 84 ms]Searching for ans.dnsalias.com ALL record at D.GTLD-SERVERS.NET. [192.31.80.30]: Got referral to ns2.dyndns.org. (zone: dnsalias.com.) [took 39 ms]Searching for ans.dnsalias.com ALL record at ns2.dyndns.org. [204.13.249.81]: Reports ans.dnsalias.com. [took 30 ms]The first place it looked was at m.root-servers.net. The root servers are there for DNS queries. The server at m.root-servers.net referred the request to d.gtld-servers.net. That server referred the request to ns2.dyndns.org, which is the DNS server that actually has the IP for ans.dnsalias.com on record. The table on the page lists the actual IP that the dynamic DNS server is reporting for that domain. So, what happened here is that the request went to one of the root servers, then got referred to a gtld server, and finally to the dynamic DNS server which gave the correct IP.If the machine at ans.dnsalias.com was switched from dnsalias.com to another dyanmic DNS service, then the only thing that would have changed in that request is the last DNS server, the request would have gone to the new company's DNS server to look up the IP.You can also notice on that table that the TTL for all of the name servers are set to a day, whereas the TTL for the single dynamic record is set to a minute. The only server that gets updated there is the dynamic DNS server, it checks again every minute so that when it gets asked it has the right address. Link to comment Share on other sites More sharing options...
midnite Posted January 11, 2007 Author Share Posted January 11, 2007 Thanks very much!! i understand thoroughly now n i can go for a .com soon :)that page has also let me know that my damn ISP is using a damn proxy -.- that's why the webpages sometime get my IP wrongly. But something funny, although that proxy is banned by DNSStuff, i can still access the page that you mentioned *sometime* by just refreshing my browser for a few times. DNSStuffWARNING: You are using a web proxy that is currently being abused by malware. Please go here for more details. The web proxy IP is 222.166.160.226. Link to comment Share on other sites More sharing options...
justsomeguy Posted January 11, 2007 Share Posted January 11, 2007 Yeah, if your ISP is putting you behind a proxy, that might make dynamic DNS a little difficult. Which ISP do you use? Link to comment Share on other sites More sharing options...
midnite Posted January 12, 2007 Author Share Posted January 12, 2007 icable, hong kong.i wonder if it is due to the taiwan earthquake days ago, that makes us clients can "go out" of hong kong ..n i wonder why it will sometimes can but sometimes get blocked ??the proxy IP is always 222.166.160.xxx , with xxx is changing nearly ALL the time .. Link to comment Share on other sites More sharing options...
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