I have several domains (websites) on the same ip address using host headers in IIS 4.0 on NT 4.0.
A few of these domains have mail capabilities. Mail is working perfectly except as noted below. IIS and exchange reside on the same box. I run my own DNS server which also resides on the same box.
Problem... any ISP that uses spam filtering based on reverse lookups fails because I have not spcifically set up reverse records for these domains. Our ISP (T-1 provider) has a reverse pointer set up that of course does not resolve to any of our domains. Thus... the emails get bounced.
I've researched the forum messages and from what I've read, I need to contact our T1 provider and let them know that I want to handle my own reverse records. So far so good? Ok, just to experiment, I tried to set up a new reverse zone based on an existing zone only to have DNS manager tell me a record already exists. However, I can't find reference to this record anywhere in DNS manager.
To complicate things, we have a "sub" class C address range. I've read that these are especially hard to do reverse records on correctly.
Then I got to thinking... since I have several domains all with the same ip address, even if I do get this set up, how would a DNS server know which domain to return when doing a reverse lookup on that ip address if there are several domains attached to the same address? Seems to me that you could only have one reverse record listing one domain per ip address. If this is the case then I would have to select the most important DNS domain mail record to set up the reverse on. Correct?
Sorry, but considering how much I've read on DNS workings, I still have more problems understanding this than any other aspect of networking. In a perfect world, I understand completely how and why DNS works, it's just when you add things like sub class C's and host headers for reverse records I get a little overwhelmed.
Any insight would be greatly appreciated! MS DNS manager specific would be a plus!
Thanks in advance!
Ken
(The confused DNS admin)
A few of these domains have mail capabilities. Mail is working perfectly except as noted below. IIS and exchange reside on the same box. I run my own DNS server which also resides on the same box.
Problem... any ISP that uses spam filtering based on reverse lookups fails because I have not spcifically set up reverse records for these domains. Our ISP (T-1 provider) has a reverse pointer set up that of course does not resolve to any of our domains. Thus... the emails get bounced.
I've researched the forum messages and from what I've read, I need to contact our T1 provider and let them know that I want to handle my own reverse records. So far so good? Ok, just to experiment, I tried to set up a new reverse zone based on an existing zone only to have DNS manager tell me a record already exists. However, I can't find reference to this record anywhere in DNS manager.
To complicate things, we have a "sub" class C address range. I've read that these are especially hard to do reverse records on correctly.
Then I got to thinking... since I have several domains all with the same ip address, even if I do get this set up, how would a DNS server know which domain to return when doing a reverse lookup on that ip address if there are several domains attached to the same address? Seems to me that you could only have one reverse record listing one domain per ip address. If this is the case then I would have to select the most important DNS domain mail record to set up the reverse on. Correct?
Sorry, but considering how much I've read on DNS workings, I still have more problems understanding this than any other aspect of networking. In a perfect world, I understand completely how and why DNS works, it's just when you add things like sub class C's and host headers for reverse records I get a little overwhelmed.
Any insight would be greatly appreciated! MS DNS manager specific would be a plus!
Thanks in advance!
Ken
(The confused DNS admin)