12 Replies Latest reply: Mar 5, 2009 8:54 PM by Jeff Kelleher
DrSupachicken Level 1 Level 1 (5 points)
Hi Guys,

The more I understand this stuff the more I seem to stuff it up. I've read over the manuals many times and through multiple posts but I can seem to get this going and I have been trying for 2 months now. What I want to do is host my own website and mail server off my computer at home.

I have ADSL2+ with three static IP addresses. I have an ADSL modem in full-bridge mode connected to a Airport Extreme with acts as a DHCP server and PPPoE authentication host, I then have a Power Mac G5 connected to the AEBS getting its IP via Mac address

So,

ADSL modem (203.206.233.251 - gateway IP) + 203.206.230.129 and 203.206.230.120

AEBS 10.0.1.1

OS X server 10.0.1.2

My domain registrar makes me have two name servers in my domain.

I set my computer up as mail-01.pushmymail.com.au

How can I create a second name server on the same computer? If someone could walk me through what I need to get down it would be so appreciated as this has got me near breaking point, If I put my foot through the computer it is one way of resolution at least.

Any help would be awesome!

Cheers,
Dave.

MacBook Black 2.16GHz 4GB 250GB 2700RPM, Mac OS X (10.5.6), iPhone 3G 16GB White
  • 1. Re: Same computer multiple IPs?
    Jeff Kelleher Level 4 Level 4 (3,015 points)
    I can't tell you how - I understand DNS to the extent that I know what it does, and I've used ServerAdmin to set up DNS for a couple LAN's.

    In any event, your Domain Registrar is requiring you to comply with RFC 2182 which suggests that you should have a secondary DNS server in case your primary goes down, thus keeping the internet working. If you're running an email server, a web server, or any other server that uses the internet you'd be asking for trouble not to have a secondary server. In general, the RFC's intend (I believe) to ensure the reliablilty of the internet. Imagine if everyone said "pfft, whatever, if my server goes down, I'll fix it".

    As for running two name servers on one box, you could probably do it via virtualization, but that would defeat the purpose of having two (or more) name servers.

    If you're not sure how to do this or what it means, I'd suggest Googling for a DNS hosting service. Based on my DNS expertise, that's what I would do (and in fact I do in real life). For folks well-versed in DNS, this is trivial. Fow me, it would be a couple weeks of banging my head on the keyboard while reading DNS & BIND http://oreilly.com/catalog/9780596100575/ which most folks consider the book to get for learning DNS.

    Jeff
  • 2. Re: Same computer multiple IPs?
    MrHoffman Level 6 Level 6 (12,470 points)
    If you're running your own DNS (why?), you'll need a second and separate computer for each.

    And each DNS server generally needs its own static IP address.

    The central rational of configuring two DNS servers is to avoid outages when one of the two DNS servers is down.

    For a few DNS translations, having the ISP translate the DNS addresses for you is massively easier than running your own DNS.

    Here, your ISP or whomever is hosting your domain information can set this up - the DNS name to IP address mapping - as part of the ISP DNS servers.

    Not unless you want to run your own DNS servers, and you probably don't want to do that.
  • 3. Re: Same computer multiple IPs?
    DrSupachicken Level 1 Level 1 (5 points)
    Thank you both so much for your replies! So I'm guessing this is what I do.

    Go to my domain registrar planetdomain.com and set the DNS for pushmymail.com.au to ns1.planetdomain.com and ns2.planetdomain.com

    That way I am using there DNS and have two nameservers.

    Now I have two static IP address

    203.206.230.129 pointing to mail-01.pushmymail.com.au
    203.206.230.130 pointing to mail-02.pushmymail.com.au

    I'm guessing that I need to create an internal DNS on the server for it to run.

    Do I create the MX record for the domain mail-01.pushmymail.com.au using planet domain DNS?

    How do I link it all up to make it work?

    Cheers.
  • 4. Re: Same computer multiple IPs?
    Camelot Level 8 Level 8 (45,790 points)
    Unfortunately some of the above answers are not quite correct.

    You do not need two DNS servers to host your domain. What you do need, as per the RFC, is two public IP addresses that remote DNS servers can query. If you follow the entire RFC it says those two servers should be on separate subnets/networks and preferably even geographically diverse.

    The spirit of the RFC (two public IP addresses) can be accomplished with a single machine and some simple port forwarding in your router - configure your router to forward ports 53 on two different machines to the same internal machine. Problem solved.

    Now, sure I can hear lots of people screaming about lack of redundancy and if that one server goes offline so does your entire domain, yada yada yada, but if that one server IS also your web server and your mail server, what difference does it make? Even if people could resolve your domain's web site or mail server address they wouldn't be able to connect since the server is down.

    That's not to say you shouldn't setup two machines - it's definitely preferable, but it isn't truly necessary.

    As for the other questions:

    Do I create the MX record for the domain mail-01.pushmymail.com.au using planet domain DNS?


    If you're planning on delegating your domain to your own servers and running your own public DNS then you setup the MX records on your own DNS servers. Planet domain no longer have anything to do with it.

    How do I link it all up to make it work?


    You tell Planet domain that your own IP addresses are the authoritative hosts for your domain (whether that's one server or two).
    Then anyone looking for a hostname in your domain is going to query your own server.
    As a result you need to populate your DNS servers with all your zone data.
  • 5. Re: Same computer multiple IPs?
    DrSupachicken Level 1 Level 1 (5 points)
    Thanks for the reply. More confused then ever now!

    All I want to be able to do is run a mail server and host a website off my server.

    Power Mac G5 ---> 10.5.5 server in advanced configuration.

    First things first, need to set up DNS.

    DNS primary zone would be my domain name? pushmymail.com.au. (FQDN) yes?

    A record is mail-01. with the IP of the machine 10.0.1.2

    Do I need to enter the public IP in the DNS anywhere?

    I need to create another A record with pushmymail.com.au so that can resolve and do I need another A record for www.pushmymail.com.au so that can resolve?

    The NS record would be mail-01.pushmymail.com.au.

    Is this all I need to do to have my domain name resolve?

    Cheers.
  • 6. Re: Same computer multiple IPs?
    DrSupachicken Level 1 Level 1 (5 points)
    I've now set the DNS from the domain registrar to mail-01.pushmymail.com.au and mail-02.pushmymail.com.au

    Doing a fresh install of 10.5 server and will set up DNS with the zone name pushmymail.com.au

    Hopefully a step in the right direction.
  • 7. Re: Same computer multiple IPs?
    MrHoffman Level 6 Level 6 (12,470 points)
    Probably a review, but... DNS gets you from the host name to the host IP address, and the translation request goes to the local servers and local caches and eventually along to the authoritative DNS servers. The remote web browser or the remote mail server would ask for "example.com" to get to your domain (or whatever your domain is) and would get the IP address from a DNS cache or from the authoritative server, then uses the returned IP address to toss the IP traffic at your server.

    In this case, the ISP is leading you toward or you're asking the ISP for the ability to run those DNS servers yourself. That's very flexible, and allows you to handle external translations and your own internal stuff. (And there are various ways to configure your DNS.)

    If your environment is big enough to be running DNS servers yourself (either in terms of host name or IP address churn and/or in terms of the scale of your local IP network), then multiple parallel DNS servers are the way to go.

    For the smaller cases, you usually don't need to run DNS server at all; the translations of a handful of static IP addresses can be hosted off your ISP's DNS servers. This gets you out of needing and running multiple DNS servers, and out of configuring and managing the DNS servers. (You do still use DNS resolvers and DNS addresses, but you use your local DNS resolvers to access the ISP DNS servers.) There are cheap DNS services around; folks that resolve your domains (and specific host names within those domains) for a fee.

    If you really want to run your own DNS servers, seriously consider reading Cricket Liu's DNS book. And do look to run multiple separate DNS servers. I have run single-server DNS configurations, but those are entirely network-internal DNS configurations. And things get ugly when (when, not if) that DNS server or the box tips over; everything using IP and DNS on the LAN then starts to fail. Which is why I don't recommend that. And if everything is all on one box, I'd put the DNS out at the ISP.
  • 8. Re: Same computer multiple IPs?
    DrSupachicken Level 1 Level 1 (5 points)
    Thanks for your reply. I'm not fussed about running DNS I just thought that I have to. All I want to do at home is run the mail server. Planet domain told me to use there DNS and put my ip address in as an mx record on there DNS. Will that work?
  • 9. Re: Same computer multiple IPs?
    MrHoffman Level 6 Level 6 (12,470 points)
    Yes. This will work.

    The MX record for the domain is where the incoming mail is sent.

    You can further establish a published host name within the domain for other network traffic (web, ftp, ssh, etc), which could well (also) go to the same IP address. A host name such as www.example.com is a common choice here; www is the usual host name for the web server for the domain.

    Most DNS providers are willing to set up MX and some number of host records in their DNS servers.
  • 10. Re: Same computer multiple IPs?
    DrSupachicken Level 1 Level 1 (5 points)
    Ok, great!

    I have set the DNS on planet domain, so I'm using there DNS.

    I have set the MX record for 203.206.233.251 so now all mail should be directed to my server, which is going to be a mail server.

    Should I create an a record for mail.pushmymail.com.au with the IP address 203.206.233.251 for webmail access? Or should I stay away from the website, I wanted to have a index screen on my website, then a different site for mail.

    ie... www.pushmymail.com.au (Index default page) and mail.pushmymail.com.au as a webmail access point.

    Thanks heaps guys!
  • 11. Re: Same computer multiple IPs?
    MrHoffman Level 6 Level 6 (12,470 points)
    Whether and how you should configure your DNS depends entirely on your goals, and on your preferences for names and routing.

    You need to figure out what names you want, and what addresses are behind those names.

    Foo.example.com can be 10.1.1.1
    Bar.example.com can also be 10.1.1.1
    www.example.com can be 10.1.1.1
    webmail.example.com can be 10.1.1.1
    Your MX record for the domain can resolve to 10.1.1.1
    Yes. All the same host.

    Or you can use...

    Foo.example.com can be 10.1.2.1
    Bar.example.com can also be 10.1.2.2
    Your MX record for the domain can be 10.1.2.3
    www.example.com can be 10.1.2.4
    webmail.example.com can be 10.1.2.5
    And your MX record can be 10.22.33.44

    Different names to different addresses.

    Or you can have a single host name resolve to several IP addresses. Google does this; www. google.com can resolve to multiple different hosts. But that's more detail than you probably want here

    Whatever you want this name to address mapping to be. It's your call.
  • 12. Re: Same computer multiple IPs?
    Jeff Kelleher Level 4 Level 4 (3,015 points)
    Camelot:

    I'm not questioning you, per se, but just trying to learn as I go.

    I agree that you don't need two DNS servers to do what the OP asked.

    My advice, because I do it myself, is that if you're new to DNS, let someone else do it. If you're going to try it yourself, either to save money, ot just because you want to, is to do it right.

    People rely on email, and in many cases web sites, and they expect and sometimes need them to work all the time. Again, I agree that you can make one machine do this all, and it may work perfectly. You can absolutely get by putting everything one server.

    The point I meant to get across is that if you try to take shortcuts, you may be sorry in the future. Reliable services require more than one server.

    If the OP is willing to accept down time when his one server goes down, then that's fine, you are correct.

    I've read many of your posts, and I know that you know what you're talking about and I respect your knowledge and expertise. I've just seen too many folks set things up with low costs in mind, only to get burnt in the end when the one server they rely on crashed.

    Peace,

    Jeff