DNS 1/2 Changed (Full Version)

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ou812 -> DNS 1/2 Changed (8/17/2005 17:05:36)

I'm taking over a site to do some enhancements. I've had the client change hosts and the DNS has been changed. Right now the http://WWW.domainname.org points to the new host but the http://domainname.org (without the WWW) still points to the old host.

I've not run into this before. What does this mean, or better yet what is going on?



ou812 -> RE: DNS 1/2 Changed (8/17/2005 23:11:23)

Nevermind. I found the problem - I'm impatient. 8 hours later both are pointing to the correct server. I've never had just one go and not the other. Strange to me.



BobbyDouglas -> RE: DNS 1/2 Changed (8/18/2005 0:21:20)

Anyone else who reads this about a DNS issue, you can try the following:

Start > Run > Type: cmd

Type: ipconfig /flushdns

Sometimes you might need to restart your computer/connection.



Giomanach -> RE: DNS 1/2 Changed (8/18/2005 15:30:34)

quote:

ORIGINAL: BobbyDouglas

Anyone else who reads this about a DNS issue, you can try the following:

Start > Run > Type: cmd

Type: ipconfig /flushdns

Sometimes you might need to restart your computer/connection.

Nope, wont work.

When transferring a domain from one DNS server to another, you still have to allow for the 8-48 hours propagation waiting time. Yes the domains are effectively the same, but they have different DNs records on the servers.



ou812 -> RE: DNS 1/2 Changed (8/18/2005 16:09:04)

quote:

Yes the domains are effectively the same, but they have different DNs records on the servers.

That's what I wasn't aware of, until this happend. Thanks.



BobbyDouglas -> RE: DNS 1/2 Changed (8/18/2005 17:58:20)

quote:

Nope, wont work.
When transferring a domain from one DNS server to another, you still have to allow for the 8-48 hours propagation waiting time. Yes the domains are effectively the same, but they have different DNs records on the servers.

- DNS changes haven't taken 8-48 hours for awhile now. Last time I registered a domain in 5 minutes...

Also, the flushdns function works when you register a new domain. I never tested it for when you change DNS, but figured it might work because the problem is with the DNS & IP.

Here is some more info on the subject: http://www.pcstats.com/articleview.cfm?articleid=1723&page=8

What problems have you ran into where it didn't work for you? Might be doing something wrong, dunno. [&:]



Giomanach -> RE: DNS 1/2 Changed (8/19/2005 15:32:57)

Bobby

That's registered, not changed the DNS. There is a difference. And the method you have provided a link to only works on the LOCAL machine, you still have to wait for the DNS servers to update and clear their own cache, so no matter how hard you try, there will alwasy be a waiting period.

quote:

What problems have you ran into where it didn't work for you

None, for I have the patience and understanding of Domains & Servers that is needed for this kind of thing

quote:

Might be doing something wrong, dunno.

When I do, I'll let you know[:-]



BobbyDouglas -> RE: DNS 1/2 Changed (8/19/2005 21:07:59)

quote:

That's registered, not changed the DNS.... there will alwasy be a waiting period.

- Think of this... The ISP refreshes their DNS sever every 24 hours (which seems to be the normal), you change the DNS of a domain, and your ISP refreshes their DNS within that 24 hr period, but it is still in your comptuer's cache, so it doens't route correctly. If you use the flushdns command, it will clear all of the DNS cache.

I called my ISP Cox to verify the above and that's what they told me.

Also, there will always be a waiting period, but if you clear the DNS cache it might lower the time to wait.

For anyone else who is reading this, you can modify your registry so that your computer will not cache failed DNS entries here. The page explains how to modify it yourself, as well provide an automatic fix if you don't feel like manually changing your registry.



Giomanach -> RE: DNS 1/2 Changed (8/21/2005 14:55:07)

quote:

Think of this... The ISP refreshes their DNS sever every 24 hours (which seems to be the normal), you change the DNS of a domain, and your ISP refreshes their DNS within that 24 hr period, but it is still in your comptuer's cache, so it doens't route correctly. If you use the flushdns command, it will clear all of the DNS cache.

I would if we were talking about ISPs, but we're not, we're talking about Domain Registrars & DNS Servers. Yes the old routing will still be in the computers cache, but you still have to wait for the DNS servers (not ISP servers) to update & refresh their records. The closer the server to the one its going to, the quicker it will update, and as you most likely use GoDaddy, all the US DNS servers will update first, and then the rest around the world.

quote:

you can modify your registry so that your computer will not cache failed DNS entries here.

But it's not the LOCAL machine that needs altering, or anything doing to, you need the strange virtue known as patience.



BobbyDouglas -> RE: DNS 1/2 Changed (8/21/2005 15:10:42)

quote:

But it's not the LOCAL machine that needs altering, or anything doing to, you need the strange virtue known as patience.

- What?!? If you have a cached DNS entry, even if the DNS servers update, you still might be going to the wrong place because of the cached entry.

Dan, you should really give this a test try and see if it works, because it works for me.



Giomanach -> RE: DNS 1/2 Changed (8/24/2005 13:42:06)

Excuse me Mr Bobby Douglas, but this is turning into an unnecessary argument. What you need to realise is, I am talking about the DNS Servers, and you are talking about the local machine. Yes, they may be linked, but in this case, what we are talking about is two totally different matters.

DNS Flush works on the local machine only, it does not work on DNS Servers. You can clear out the DNS on the local machine, but still be directed to the old site. You still have the 8-48 hours propagation waiting time on the DNS servers. Upon this matter, you have contradicted yourself already:
quote:

DNS changes haven't taken 8-48 hours for awhile now. Last time I registered a domain in 5 minutes...


Brians original question was about the two domains not changing at the same time, his second post states that all he needed was some patience, and it now works. The 8 hours gap is the propagation period needed for ALL DNS servers to refresh & update records.

This will always be the case regardless of whether you have cleared the local cache or not. The changes & updates in DNS records can take seconds, they can take days, it depends on where you are, and where the server is in the world. Therefore, patience is required.

And for the record, I keep no DNS cache on my machine, I keep no browser history and no browser cache, and I still receive the problems that Brian posted about above. So its not my cache that gives the waiting time, it's the propagation period.

Please read my posts more carefully, and in their entirety for full understanding, and the actual meaning of what I am saying.

My case is closed.



BobbyDouglas -> RE: DNS 1/2 Changed (8/24/2005 14:26:22)

quote:

Excuse me Mr Bobby Douglas, but this is turning into an unnecessary argument.

- Just trying to understand where you are coming from, if you don't want to take the time to prove your points, just say so and I will let it be.

quote:

What you need to realise is, I am talking about the DNS Servers, and you are talking about the local machine. Yes, they may be linked, but in this case, what we are talking about is two totally different matters.

- The flushdns command is only for the local machine. (I never said it afffects the DNS servers) But that doesn't mean it won't help with propagation. If the DNS servers update, and your computer still has the previous ones cached or a failed attempt cached, then you will still go to the wrong dns.

They might be two different matters, but there are similar in the sense that the local cached DNS affects where you go, and even if the DNS server updates, and your local dns is cached, you still have a great chance of going to the wrong place.

quote:

Brians original question was about the two domains not changing at the same time, his second post states that all he needed was some patience, and it now works. The 8 hours gap is the propagation period needed for ALL DNS servers to refresh & update records

- [Read above] there is still a chance that the DNS has been cached & thus can take longer if you don't use that command.

quote:

This will always be the case regardless of whether you have cleared the local cache or not. The changes & updates in DNS records can take seconds, they can take days, it depends on where you are, and where the server is in the world. Therefore, patience is required.

- Where have I argued that patience is not required? I am just saying that by clearing the DNS cache, there is a greater chance that you will be able to see the DNS changes quicker. I have provided a link that explain this to backup my points.

quote:

And for the record, I keep no DNS cache on my machine, I keep no browser history and no browser cache, and I still receive the problems that Brian posted about above. So its not my cache that gives the waiting time, it's the propagation period.

- Of course there is a propagation period, but once again, if you still have the previous DNS cached, it will affect how long it takes for you to see the new DNS. Why are you talking about browser history/cache?

quote:

Please read my posts more carefully, and in their entirety for full understanding, and the actual meaning of what I am saying.

- What did I not read? You just keep repeating the same thing about patience, but nowhere have I argued that you don't need patience.

In fact you said it again right here:
quote:

But it's not the LOCAL machine that needs altering, or anything doing to, you need the strange virtue known as patience.


....yet the link I posted earlier says otherwise.

You can keep on saying "you need patience" but if you are not going to explain how my logic is wrong, your arguments will continue to have no strength.



ou812 -> RE: DNS 1/2 Changed (8/24/2005 16:12:09)

Not to butt in on your discussion, but I think I will since it was my question! [;)]

I think you guys are agreeing on everything except from what I believe Bobby is trying to point out on using FlushDNS. You both agree the need for propagation and the patience needed. Bobby is additionally adding that even though propagation may have completed, your local machine may still not point to the correct server because you may need to flush your local DNS. And, this flushing wouldn't help if the propagation has not occurred.

In my case, I'm guessing the flushDNS command would not have worked (although, I wish I would have known about it to give it a try. Or at least had the smarts to use the computer next to me!) for me. I'm thinking that since one name was propagated as well as changed on my local machine that the other would have changed on my local machine too, if it did propagate. So, patience was the answer in this case. At least that is my guess.

I appreciate both of your input and help, and always enjoy reading the different thoughts and technologies.



jaybee -> RE: DNS 1/2 Changed (8/25/2005 6:01:06)

quote:

DNS changes haven't taken 8-48 hours for awhile now. Last time I registered a domain in 5 minutes...


I've recently had two take around 15 minutes but I also had another that took 2 days. All 3 were bought within 15-20 minutes of each other.

I've also found that moves take longer, typically 6 hours or more. I never bank on any of them being there for at least 48 hours to be on the safe side. After 48 hours I'll chase them up.



BobbyDouglas -> RE: DNS 1/2 Changed (8/25/2005 17:22:01)

Jaybee, did you visit the domains before you registered them?

I sometimes visit the domain before I register it, and once you visit it, it caches the failed attempt, so you have to restart or run the flushdns command.



caz -> RE: DNS 1/2 Changed (8/26/2005 8:44:40)

I see that this same horse is being flogged elsewhere, with the same answer...
http://www.webmasterworld.com/forum25/3057.htm

[8|]



jaybee -> RE: DNS 1/2 Changed (8/26/2005 9:48:03)

quote:

Jaybee, did you visit the domains before you registered them?


No. Never do. It caches the failed attempt. [;)]



BobbyDouglas -> RE: DNS 1/2 Changed (8/26/2005 12:59:16)

quote:

ORIGINAL: caz

I see that this same horse is being flogged elsewhere, with the same answer...
http://www.webmasterworld.com/forum25/3057.htm

[8|]

-Same answer? jmccormac is talking about how DNS works, it seems that he misunderstood the main question about the local cache.

quote:

No. Never do. It caches the failed attempt. :)

- I just installed the registry change so that it wouldn't cache that anymore, and it appears to have worked.



Universal4 -> RE: DNS 1/2 Changed (8/26/2005 23:18:52)

I recently got a new client from South Africa.

She first purchgased a new domain and hosted it with me. I could access the site in a matter of hours of her buying the domain. She could publish to it from SA the next day.

About 2 weeks later she moved 9 more sites to me. About half were accessable in about a half day after the dns change and the rest took until the following day. (for me)

All sites took one extra day for her to access. What was strange was a few of the www.'s actually took an extra day than the non www. I think it had to do with the previous host using A records instead of an Alias for the www.

With a little creative editing of my host file on one of my workstations, I had all 9 sites Published to the server before we changed the dns.

BTW, I am in Central FL

Rick
Universal4



BobbyDouglas -> RE: DNS 1/2 Changed (8/27/2005 0:54:01)

quote:

With a little creative editing of my host file on one of my workstations, I had all 9 sites Published to the server before we changed the dns.

- Most hosts setup something along the lines of http://serverip/~username for temp access to a site, so you can FTP all the files needed.

About the other points, I don't see how they relate to the issue about FlushDNS...



Universal4 -> RE: DNS 1/2 Changed (8/28/2005 20:29:08)

Routers and switches owned and opearated by the backbone providers around the world update and flush their resolver caches at different intervals as well as peering times for root servers. (although peering of root servers happens much more frequently now as opposed to what it was a few years ago)

I gave my above example as a "real-world" example to help show how resolving dns can be different around the world.

In my example, flushing dns of a local workstation had absolutely nothing to do with resolving the sites.

The original post had to do with domainname.com and www.domainname.com and I have seen this quite often when moving sites.


Rick
Universal4



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