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Secondary DNS server

J

jerry2

Guest
Hi there

I am using a root server dedicated with Plesk... Now I want to have my DNS server for my domain names and I was reading everything I could find. Quite complicated stuff... The question is what is best to do in my situation. I have 1 IP only on this server. I can buy 1 or 2 more.

1. I can buy 1 or 2 IP's (I couldn't find anywhere if 2 IP's are enough for hosting and DNS servers or 3 are needed). Then I can set my DNS server on the machine and I live happily ever after. I wish... Problem is if my machine goes down the DNS server also goes down and I can not set up another machine or redirect visitors to tell them we have problems...

2. Another option is to leave management of DNS servers to another company like EasyDNS.com. Then I have all control, spend money in them instead of 2 extra IP's. If I go down I can easily manage DNS records. If they go down I am in trouble :-(

3. I can buy for the money of 2 IP's (10 EURO) a Virtual Server with 200Gb bandwidth and max 100 users on it. As it also has Plesk I think that it could be set up to be the DNS server also and I could exchane the DNS with my root server using Plesk (is that possible???). If my server goes down I still have secondary DNS and I guess I can reroute DNS entry to some other site.

4. I can perhaps use my 1 IP to set primary DNS on my root server and use another service to have secondary DNS (and update the zone).

What is the preffered method that you use for the DNS server dilemma? Another question is the option 4. possible in Plesk? Can Plesk be set up that exchanges zones from outside? I guess this is also relevant for setting another server and exchanging DNS with each another. How to do it? Using Plesk for everything really simplifies things, doesn't it? Using another DNS provider is more complicated to manage...

If there are any ideas, please feel free to answer.

Yours

Jerry
 
I think most of those scenarios you described are valid, but it all depends on what level of redundancy you want. I also think you have to look at the big picture and not just DNS redundancy. If your server goes down that is hosting DNS it's likely that the website is down as well, so whats the point of DNS working when there is no website/server to go to anyway.

We use our domain registrar for DNS, which gives us a layer of redundancy becuase they are seperate from our server. But it also puts our trust in the domain registrar that they won't have a major meltdown.

probably the best thing to do is to run at least two DNS servers on different networks all together. Whether that is a combination of your root server and/or some third party server at a different host or just two root servers is up to you. But the more diverse the better.
 
Thank you for your opinion. Yes I agree. If I don't have the site, what is the point of having DNS. Just that I can change the DNS records and point to some other small hosting and put a textfile we are down so people don't call me. That is a lot for me...

But instead of paying 5 EURO/month for a second IP I would rather buy 25 DNS'es managing service for the same price and use it as a secondary service.

But... I don't know how to set this in Plesk. Is Plesk able to send zones to 3rd party provider? What requirements must he meet?

And then, how to set the master domain? I can set plesk to use ns1.mydomain.com and instruct 3rd provider to use ns2.mydomain.com, and change this info at registrar, but it won't work I guess. 3rd party won't be able to get zone until everything is working and until he get's the zone, registrar won't be able to enter his ns2 as it won't be working.

Or maybe I am missing something?
 
Our thinking is that for 1 server if you have 2 IPs then the most appropriate method is to use the server and its IP as your primary dns server and your second IP as a virtual dns server. If you have only 1 server then dns redundancy is pointless.

If you have only 1 IP or don't want to buy an extra block of IPs then you should get another dns host (someone with the same resources as you) to run secondary DNS for you. You can usually accomplish this by using a DNS exchange deal, they do it 4 u, u do it 4 them. This works well, plesk is ready for you to run secondary DNS somewhere else and is as easy as adding a server IP to your ACL to enable zone information transfer.

To run secondary DNS for them you will need to install something like ART's secondary DNS system.

If you have multiple servers you can get a bit more clever using load balancing and either run your websites with full redundancy or use an information page to say the server is down.

Another alternative is a DNS management service like zoneedit.com. This does everything you will want, but clever services will cost a small amount per domain.

Let us know what you decide to do.
 
Thank you for your advice. I forgot to mention I am a mini company and hosting 10 small customers (restaurants) and my page which is quite large for our country, but small in worldwide (100.000 users monthly)...

What don't have the funds to have server balancing or other more fancy stuff. What I would need is ability to make an announcement site is down if something happens. That's all. But as far as I understand I can not get that using 2 IP's and only my server...

I am thinking more about the possibility of having 1 IP for primary DNS on my server and instead of buying second IP (5 EURO/month) to invest something in a ZoneEdit or simmilar service who offers secondary DNS service. I pay about 1$ per domain and still manage my DNS using Plesk. If site is down I can go to secondary DNS provider and enter another temporary IP for that domain and users would see a notice of site being down.

Now is that managable in Plesk? I am quite a beginner in this and I don't realy understand what did you mean by:

"...adding a server IP to your ACL to enable zone information transfer.."

Is that possible with Plesk or should I edit the conf file and add the IP of the secondary DNS provider who can then query for my zone? Sorry, as I said, I don't know how to do it...

So if this is possible I would say my registrar to enter in the primary and secondary services:

ns1.mydomain.com
ns2.secondaryprovider.com

and enter ns1.madomain.com in Plesk using the DNS settings and wait 72 hours... And of course the mystery part how to open my Zones to the outside provider. But is that the correct way to do it?

As I found out, until I have my primary domain working with it serving as DNS server I can not add clients's domains and subdomains myself.

Yours

Jerry
 
Originally posted by jerry2

....... Now is that managable in Plesk? I am quite a beginner in this and I don't realy understand what did you mean by:

"...adding a server IP to your ACL to enable zone information transfer.."
If your server is setup for secondary DNS to be hosted on someone elses server you need to grant the other server access to your DNS zone information. You do this by adding the IP address of the other server in your DNS Access Control List (ACL).


Is that possible with Plesk or should I edit the conf file and add the IP of the secondary DNS provider who can then query for my zone? Sorry, as I said, I don't know how to do it...

Above is the reasoning and method, specifically - select the DNS icon from the server page and select "Common ACL" pop the IP address of the other server in there.


So if this is possible I would say my registrar to enter in the primary and secondary services:

ns1.mydomain.com
ns2.secondaryprovider.com

and enter ns1.madomain.com in Plesk using the DNS settings and wait 72 hours... And of course the mystery part how to open my Zones to the outside provider. But is that the correct way to do it?

Yes this is what you would do with your registrar. What you do on plesk is make the server authoritive for the dns server domain, in your example mydomain.com or ns1.mydomain.com. In the DNS zone for mydomain.com enter an A record for both servers and if you are hosting anything on the domain then enter your two nameservers in your nameserver records. For every other domain and in your DNS template you need to enter both primary and secondary nameservers as above.

NOTE: The default PLESK DNS zones will need to be changed. This is not wild advice, I have done all examples provided and found the problems and how to countermeasure.

Let us know how u go.
 
Thank you again...

So I can do that using Plesk, no need for editing the special file in Windows? But adding IP has option to add 8, 16 or 24 and in the ionstructions I can not find what it is.

So if I understand you, ANY web provider of DNS services can take my Zone from my server if I let him to?

But the first thing must be to say provider my server nameserver and secondary sever company nameserver? Because the master domain doesn't work now before this info in inside, but the info points to the nonexistant nameserver on my server and the secondary server that didn't get my data yet because it doesn't work yet. Seems like kind of chicken and egg situation, I just guess it works somehow.

So you would say using secondary DNS service for the same money as buying second IP is better than running DNS server entirely on my machine (no option to set the failure message).

What is wrong with default Plesk DNS templates? I don't like that everything I enter in www browser (any subdomain of my site) it comes to the Plesk interface somehow.

Yours

Jerry
 
Originally posted by jerry2
Thank you again...

So I can do that using Plesk, no need for editing the special file in Windows? But adding IP has option to add 8, 16 or 24 and in the ionstructions I can not find what it is.

Well I am running linux but no special filese need editing for me. The owner of the other server will be able to tell you his network type to select the appropriate option.


So if I understand you, ANY web provider of DNS services can take my Zone from my server if I let him to?

Yes .... but to do it they may need a special utility. In plesk you can run secondary DNS somewhere else, but to run secondary DNS for someone else you will need a to use a utility available from ART.



But the first thing must be to say provider my server nameserver and secondary sever company nameserver? Because the master domain doesn't work now before this info in inside, but the info points to the nonexistant nameserver on my server and the secondary server that didn't get my data yet because it doesn't work yet. Seems like kind of chicken and egg situation, I just guess it works somehow.


The above is a little difficult to understand, but I will take a few guesses. At your registrar, you need to delegate two nameservers for your server domain. Your primary will be eg. ns1.mydomain.com - <som.ipa.ddr.ess> and secondary ns2.someotherserverdomain.com - <som.eot.her.ip>


So you would say using secondary DNS service for the same money as buying second IP is better than running DNS server entirely on my machine (no option to set the failure message).

Well if you only have one server this is fine. Having seperate geographically dispersed servers is better in any case, but the issue is that if your server goes down, you lose the sites anyway. Unless DNS is managed externally, there is no way to pop a message page on the end of the domain.

If you use the zoneedit service, you can either use load balancing by creating 2 A records and they alternate. Or you can use advanced features such as failover where the service pings your server IP every 10 minutes and if it sees your server down it will switch to an alternative server where you either have duplicate sites or error messages. It also provides a store and forward service for email.


What is wrong with default Plesk DNS templates? I don't like that everything I enter in www browser (any subdomain of my site) it comes to the Plesk interface somehow.

The default template calls the nameserver "ns" and does not specify a secondary.

If you get the default page it is because there is a DNS problem. The fact you get your server page says that your server is authoritive, but there is obviously some problem. In the zone file for the domain, make sure there is at least an A record for the subdomain as well as the other obvious stuff for the domain itself.
 
Thank you again...

But what if I run primary DNS at my server and secondary at someone else? If primary goes down the secondary pops in, is that true? So in zoneedit.com I can still point to somewhere else even if it is only a secondary DNS (I would prefer having all the data in Plesk and backing it up).

So the 8, 16 and 24 are the types of the connection?

I know more than one servers would bre great, but $$$... Maybe about the future... But I don't understand how load balancing could work if one has a mySQL data any fully dynamic data... The database must be only one, doesn't it?

Thank you for all your help.

Yours

Jerry
 
Originally posted by jerry2
Thank you again...

But what if I run primary DNS at my server and secondary at someone else? If primary goes down the secondary pops in, is that true? So in zoneedit.com I can still point to somewhere else even if it is only a secondary DNS (I would prefer having all the data in Plesk and backing it up).

If you only have 1 server running your sites it is academic. If you run DNS externally you have many switching and monitoring options.


So the 8, 16 and 24 are the types of the connection?

OK you asked, this is the implementation of IPv6.

Internet Protocol version 6 (IPv6) is a network layer standard used by electronic devices to exchange data across a packet-switched internetwork. It follows IPv4 as the second version of the Internet Protocol to be formally adopted for general use.

IPv6 is intended to provide more addresses for networked devices, allowing, for example, each cell phone and mobile electronic device to have its own address. IPv4 supports 4.3×109 (4.3 billion) addresses, which is inadequate to give one (or more if they possess more than one device) to every living person. IPv6 supports 3.4×1038 addresses, or 5×1028(50 octillion) for each of the roughly 6.5 billion people alive today.

If you have a server, you will know this setting.


I know more than one servers would bre great, but $$$... Maybe about the future... But I don't understand how load balancing could work if one has a mySQL data any fully dynamic data... The database must be only one, doesn't it?

Either both use a seperate database server, or my favourite method is "Replication". Simply, if you have two servers running the same content, then the two DBs synchronise periodically.

This can be done with replication software, or as I do it, with Coldfusion scripts.
 
Hm, how can you replicate a database using forum? Users write to it every minute.

I was thinking about DNS and here is my direction about what I was thinking and also about sites redundancy. But still I have an open question.

My solution:

I have one dedicated server and I will buy one more Root VS or another less powerfull dedicated server...

I will have on both running DNS servers so on main server I would have primary and on second I would have secondary DNS... This is possible yes? I just have to telll somehow that secondary DNS takes data from primary DNS. I will be running Plesk on both machines, so I guess one can do that...

Now what I would like to do is this... If primary dedicated sever fails for whatever reason that the DNS shows to the secondary one to show at least the backup static pages.... But how can I do that? As I understand secondary DNS is just a copy of primary one, isn't it? So when my primary fails the user browser will be searching seconday DNS server on my backup machine but there will be sites pointing to the main machine as there is only a copy of the main DNS...

So any ideas in which direction I have to think about having that minimal redundancy so that the sites from backup server (which is also secondary DNS) show up to users? Of course I could bug the registrars to change the primary and secondary DNS in all my client domains but that takes up to 72 hours and I am sure this is not the correct way to do it properly.

Any ideas would be great

Jerry
 
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