Well, the tried and true method is to add the subdomain to your dreamhost hosting account:
Step 1: Add the parent domain to your account, but don’t host it
- In the panel, go to “Domains>Manage Domains”.
- Click on “Add New Domain / Sub-Domain”.
- Fill in the parent domain name yourdomain.tld as a fully hosted domain. The settings don’t really matter. Click on the button to add the domain now.
- Go back to “Domains>Manage Domains”.
- Column 3 of the table of domains should be labeled “Web Hosting”. Click on the delete button for the domain that you just added. This will delete the hosting for that domain but will leave the domain as managed under your account.
Step 2: Add hosting for the subdomain
- In the panel, go to “Domains>Manage Domains”
- Click on “Add New Domain / Sub-Domain”
- Fill in the subdomain that you actually want to host here at Dreamhost.
Step 3: Find the IP address for the subdomain
- In the panel, go to “Domains>Manage Domains”
- In the first column of the domains table, find your subdomain.
- Click on the “DNS” link for your subdomain.
- Down at the bottom is a table of DNS records. Look for the A record for your subdomain. The “value” of that record is the IP address you need.
Step 4: Add a subdomain “A” record at your other domain registrar.
I can’t really give a step-by-step guide here because I’m not familiar with your other registrar. You should just be able to add an “A” record for the subdomain. The name of the record should be forum or www.forum, the type should be “A”, and the value should be that IP address you found it Step 3
3 extra lifetime domains and (the new maximum) $50 off with code [color=#CC0000]3DOM50[/color]. More Dreamhost coupons