PPTHost changes from Apache to Nginx

[mersh]

4. Go to my registrar and make the changes to my name servers. Depending on who your registrar is, this can take anywhere from 1-72 hours......One thing to note, never name your servers with the same name as your name servers. Always use a name that is different, such as server1.server.com, etc.

Actually what I did was changed the dns on one of the name servers (secondary specifically) so that in theory there won't be any down time. I did name the second server the same name as the ns2 - but I believe you when you say I shouldn't. Been doing it for a year now, hasn't SEEMED to harm anything... but I can see where confusion can set in.

I figure by moving only one name server at a time, "the internet" will look to the secondary only in case of failure of the primary. When I know the secondary ip address has propagated, I'll kill the first, so dns will then be handled by the second and it will refer requests to the new server. Meanwhile, I've set all the dns records on server one to point to server two (execpt the ns1 record) so if any changes are made, they'll be to the "correct" website. As soon as I did that, within minutes the sites started pinging to the new server.

I appreciate your reply a lot, at least I know I'm on the right track. Now if this server2 ip address would just go ahead and propagate for me then I'll be in business.

[bplex]

It probably never will. To do it your way requires a bit more than just changing where "ns2" points at the registrar level. When dealing with DNS, there are actually two parts: FDNS, and RDNS. At the registrar level, when you create name servers, what you are actually creating is RDNS (or reverse DNS). This allows for the root DNS servers to have a starting IP address for which they can get more DNS information on a domain (FDNS). They follow the starting point in order. So, the root DNS will contact whatever is listed as primary (your NS1). When it gets there, it contacts the DNS server there and pulls listing for everything else. If NS1 were to fail (or be shutdown), the root DNS will still contain a cached copy of the DNS available from NS1 until the TTL expires. It is at this point that the root will attempt to contact NS1 to revalidate the records. If it fails to contact NS1, it then looks up the domain root (from the registrar) to see if there are other name servers listed for contact. It is at this point that it would find NS2 and would attempt to contact NS2. Doing it this way will result in downtime as you have to wait for the TTL before the root DNS will start looking for secondary name server. Regardless of whether or not you are a root DNS or a secondary DNS (most ISPs, open DNS servers, etc), DNS traffic all work in the same manner. In order to do it your way, you would have to do the following:

1. Send out an email to your users letting them know that you are changing servers and that during this process, they may experience a brief delay as everything changes over. Tell them that this is normal and that everything should be fully restored in about 24-72 hours. You still have to do this as not all DNS servers operate equally. There could still be periods of downtime.

2. Disable the ability for your users to change their files.

3. Copy everything over to the new server.

4. Go to you registrar and change the value for my NS2 record to point to you new server.

5. Go to your first server and update all of your domain name's DNS records to point to the new server for A, NS, and MX records. For example:

example.com IN NS ns2.exampleserver.com.
example.com IN A 123.123.123.123.
example.com MX 10 mail.example.com.
mail.example.com IN A 123.123.123.123.


Where "123.123.123.123" is the IP on the new server for which the domain will reside. You will need to change every A record to point to the new server as well. You will need to remove any NS records that point to the old server.

6. Wait 24-72 hours.

7. Ping your domains from multiple locations and check to be sure that they are in fact pinging the NEW IP address and not the OLD IP address. Also, perform nslookups to make sure that the NS is pointing to NS2 and not NS1.

8. Recopy all of your data from the old server to the new to be certain that you haven't missed any changes that may have slipped through the cracks.

9. Shut down the old server.

[mersh]

funny... that's actually pretty much exactly what I did.... except for the second copying of data. I own most of the sites on the server, and the customers I do have, have pretty much static web sites. It seemed that within an hour of adding the A records on the first server, the sites were pinging to the second one. I was thinking though that I can't turn off the first server, until I see the second ns2 value pinging to the new server.

Meanwhile, the first server company offered me an upgrade to quad core servers (I'm on dual core) with twice the drive space and bandwidth, at the same price, to try to get me to stay. I may take them up on it.