One server-3domains-2 sometimes unreachable for some

[Nordinho]

Hello,

I've got an issue where 2 domains on a server can't be reached sometimes by some people. It works for 95% of the other visitors of those sites.

Situation:
Dedicated server, initially set up for one main domain. Added 2 extra domains (for clients) besides the main one later on. Those domains work fine for 95% of visitors, however I got some reports that some people can't reach the site (page unavailable).

Doing some investigating, it seems that those people are on the same isp. The weird thing this that they can reach those domains sometimes. For example; This afternoon those domains we're unavailable. Last night they could be reached. The afternoon before they couldn't

I'm thinking it has something to do with the in-addr.arpa setting. On the main domain it is configured. On the others not. (I'm no expert)

Main domain config:

ftp A 83.xxx.xxx.xxx
localhost A 127.0.0.1
mail A 83.xxx.xxx.xxx
maindomain.net. A 83.xxx.xxx.xxx
pop A 83.xxx.xxx.xxx
www A 83.xxx.xxx.xxx
maindomain.net. NS ns1.maindomain.net.
maindomain.net. NS ns2.maindomain.net.
mail MX 10
xxx.xxx.xxx.83.in-addr.arpa PTR www.maindomain.net.
maindomain.net. TXT "v=spf1 a mx ip4:83.xxx.xxx.xxx ?all"

Domain 2

ftp A 83.xxx.xxx.xxx
localhost A 127.0.0.1
mail A 83.xxx.xxx.xxx
pop A 83.xxx.xxx.xxx
domain2.nl. A 83.xxx.xxx.xxx
smtp A 83.xxx.xxx.xxx
www A 83.xxx.xxx.xxx
domain2.nl. NS ns1.maindomain.net.
domain2.nl. NS ns2.maindomain.net.
mail MX 10
domain.nl. TXT "v=spf1 a mx ip4:83.xxx.xxx.xxx ?all"

Domain 3 is setup exactly as domain 2.

Any pointers or idea's?

 

[scsi]

You have no control over ptr unless your isp has forwarded the requests to your dns server. You should do more checking. Is it they cannot reach the website or can they not resolve the domain name? These are to way different things. Next time it happens have them try to ping the domain name from the command prompt. As long as your server allows ping requests. If they cannot resolve the domain then they wont be able to ping it. Then you will know it is a dns problem and not a problem with the webserver.

 

[Nordinho]

I let one of them ping it yesterday afternoon, and it gave an invalid trace for him. (tried it myself and it resolves perfectly)

 

[nobaloney]

We can't reallly help because we have no idea how. For more information please look here.

You should have your user do a traceroute (tracert on Windows systems) to the domain when it doesn't work, and later when it does work, and send you the traceroute outputs; you may be able to see the problem then.

Jeff