DNS Resolution Issue

[netadmin06]

Hello I have a Win 2k Server as a Domain Controller....however our website is not being hosted by us, a third party is doing it... so when client computers from inside our network go to

http://www.mydomainname.com

they get an error. To solve this issue I created a host record in my dns server pointing my domain name to the ip address of the company hosting our website..this works great...my problem is that the third party company is also hosting our email and our pop3 servername is "mail.mydomainnmae.com so when i set this up in out look it does not work....if i use the ip address of the pop3 server name in outlook instead it works...when i do a ping to mail.mydomainname.com i get 100% loss but when i ping the mail server's ip address it works....i tried setting up an host in my dns server to point mail.mydomainname.com to the ip adddress like i did for the website but this has not worked...help please??

 

[nsantin]

you need to create an MX record for your domain within your local DNS zone. This way mail clients know where to send mail too.

Alternately, you can scrap the DNS zone and add the web domain to your client HOST files, depending upon how many clients you have.

 

[Cstorms]

Also I am sure that your web host is not allowing icmp echo requests so that is why you are receiving loss.

 

[netadmin06]

when i try to creata a new mail exchgner record it is asking me for a host or domain and a mail server....im a little confused....what do you enter under host or domain? should i enter mydomainname.com?? what do i enter for mail server??...how does the server know to associate mail.mydomainnamecom with my isps email server ip??

 

[netadmin06]

i am receving loss because of a dns issue in my wind3k server im sure....if i ping by ip or mail server name from a differnt network it works fine.....

 

[netadmin06]

i thought MX records can only point to domains not IP addresses?..........i need to point mail.mydomainname.com to an ip address.......

 

[nsantin]

Create an A record for the IP of the Mail server. Then create a MX record(s) using that A record.

 

[nsantin]

BTW, the MX record should be for the SMTP server, this MAY be different from the POP3 server.

Assuming they ARE different, then you need to setup 2 A records: i.e.
pop.domain.com = IP of the POP server
mx1.domain.com = IP of the SMTP server

Then, create an MX record that reference MX1.doamin.com

If you are receiving mail via POP, then make sure the name you use for the pop A record matches what you have already configured in your mail client(s), otherwise you will need to re-configure everyone.

The MX record tells a mail client where to SEND mail (SMTP), the A record tells the mail client what address the POP server is to RECEIVE mail (using POP). Im assuming you are not using a local mail server.

 

[netadmin06]

im not having issue with sending email (isp's smtp server) because the name is different (relay.mysip.com).................. im having problems with incoming email pop3 because the name is mail.mydomainname.com

 

[netadmin06]

since I am not having issue with smtp at all does that mean that i only need to setup an A record for the pop3 server?...what is an A record? Is that the same as Alias record??

 

[netadmin06]

i do not see an option to create an A record........only alias, host, cname, mx etc but no A record

 

[Cstorms]

It is the host file.. when you right click on the zone and see the "New Host (A)..."

 

[netadmin06]

i created a new host file that points mail.mydomainname.com to my isp's ip pop3 server address but still when i try to ping mail.mydomainname.com i get the error "unkknown host mail.mydomainname.com"...........but when i ping the ip address it works fine

 

[Cstorms]

what ip do you get when you ping it by the host record name? Is it the same as the one you enter manually? You may have to /flushdns to clear the cache. When you ping this name you should be getting whatever your dns server has for that name. (Assuming you have that dns server configured on your nic)

 

[netadmin06]

when i ping the host record name is get the error "unknown host mail.mydomainname.com"

the host record is created
when i ping the ip address it works fine

 

[nsantin]

When you create the Host/A record, make sure you ONLY name it the prefix, not the entire thing.

In you case, your host will be called "MAIL" , not "MAIL.domain.com"

You do not need to create the MX record(s) if you are sending to your ISP as a relay.

Also, as Cstorms said, make sure your clients are pointing to the correct DNS server, NEVER have a client point to an external DNS server when you have your own internal DNS server. (especially in a Windows environemnt)

 

[Cstorms]

What do you get when you do a nslookup for mail.yourdomainthing.com, are you sure you are using your dns server to resolve these queries? Double check your configured nic settings to be sure this is true.

 

[netadmin06]

nsantin you are 100% correct!....i created the host naming it only "mail" and now it is working great!...i was using mail.mydomainname.com before.....THANKS!!