Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I'm considering moving some clients to Google Apps Email and I'm concerned about potential email downtime. Assume that the domain is hosted on a VPS, and the MX records pointing to Google are also setup on the VPS.

A selling point for Google Apps is the separation of email services from potential downtime of the website on the VPS (all downtime is bad but email downtime IMHO is worse than website downtime).

If the VPS containing the MX records for each domain (set in cPanel for each individual domain) were to go down, would Google Apps Email also go down because the MX records -- on the VPS -- would not be available?

Is there some caching of MX records?

Thanks.

share|improve this question

1 Answer 1

The MX records are handed out by your domain's authoritative name servers. So if your VPS goes down, literally nothing happens unless your VPS is your only nameserver. If that's the case, you want to setup a "secondary" nameserver and add another NS record to your domain's zone file to advertise it. If you have two nameservers and one goes down, your email will still work because Google Apps will still be up, and your second nameserver still replies with the correct MX records.

share|improve this answer
    
Thank you for your reply. Would I need to setup a cpanelDNSonly install on a different VPS, or is there another service that could "hold" an extra nameserver record like dyn or a dns service? Also -- if I used a service like dnsmadeasy.com, would I need to setup just my VPS's domain, or would I need to set something up for EACH domain that I host on the VPS. Thank you! –  HelpSpa May 24 '12 at 18:29
    
You may want to read a bit about how DNS works, because I would have no clue about control panels to do it automatically. They slow me down and I would rather use the command line. Try zytrax.com/books/dns for DNS information/Bind setup. Essentially you buy a domain from a provider, that provider allows you to set the nameservers that are authoritative for that domain, and you can have as many nameservers as you want. Each nameserver holds a copy of the zone, which happens to include the nameserver records. MX records are part of the domain's zone file, which the nameservers use. –  gparent May 24 '12 at 18:33
    
A nameserver may also hold the zones of more than one domain (or it could also be not authoritative on any domain at all) –  gparent May 24 '12 at 18:33
    
You may also want to verify that the VPS is actually the nameserver. Your control panel may be setting up the zone record on multiple nameservers provided by the service provider. –  Justin Higgins May 24 '12 at 19:19
    
Yep, it's very important to understand the distinction between what the NS records say, which name servers you are actually running, and what your domain provider is telling the internet about your domain's nameserver settings. –  gparent May 24 '12 at 20:02

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.