Friday, September 23, 2011

DCPromo error when removing a child domain

I set up a child domain in our lab at work. The child domain controller was a virtual 2008 server. When I tried to run dcpromo to get rid of it, I got the following error:

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Active Directory Installation Wizard
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The operation failed because:

Active Directory could not transfer the remaining data in directory partition
CN=Schema,CN=Configuration,DC=xxx,DC=NET to domain controller yyy.xxxx.NET.

"The RPC server is unavailable."
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OK
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After pouring through Google and tons of forums, I could not find the answer, but everything seemed to point to it being a DNS problem. It turns out, that was indeed the case. On the parent domain controller, I opened up DNS and navigated to the child domain under forward lookup zones. I tried to ping the FQDN of the child domain controller but could not, however, I was able to ping it by computer name.

When I opened up the properties of the child domain in DNS, the name server listed for the child domain controller had its old IP address listed. So I changed it to the new IP address, and suddenly, all of the RPC errors went away and I was able to demote the child domain controller and remove the child domain!

It took me months to figure this out, and all the trouble was because the IP address of the domain controller changed.

Tuesday, July 19, 2011

Postfix Server

I was testing a monitoring program at work that generates a lot of email, and rather than bog down my company's email server, I wanted to set up my own. I decided to throw Postfix onto my Fedora VM. It seemed like a pretty basic install - just 'yum install postfix' and then edit the configuration file (main.cf). (I used the tutorial I found here.)

However, once I did this, I still wasn't getting any of the emails I was sending to myself through telnet. Hmm, was the domain set up correctly? Yup. I should have been getting email. (I set it up on a local domain, since I only needed to send email from one computer that was inside the network.)

After setting up Postfix and Cyrus (for POP/IMAP) on my ClearOS VM, that has a GUI for this sort of thing, I was able to compare its configuration file and figure out what I was doing wrong. It turns out that the 'mydomain' field in Postfix has nothing to do with the domains it accepts email for. Instead, you have to add the domains you want to accept email for under 'mydestination'.

That only took a day to figure out...

Sunday, March 13, 2011

Old Computers

Wow, I can't believe it's been over a year since my last post.

I've been trying to figure out to do with three of my computers. Currently, I have a Sempron 3300+ with 512MB of RAM that I use to watch videos on my TV. Since I use my Xbox for that now, I've been thinking about repurposing it, but my Xbox doesn't play HD video, so I'm not sure I want to get rid of it just yet. That being said, most of my video is not HD, and I hardly ever use it. So I don't know...

I also have a Pentium 4 1.7Ghz with 1GB of RAM that I installed Fedora 14 on. I could use it as an Apache server, but I already have a web hosting account with Godaddy. Perhaps I could put some kind of web app on it or use it for testing. I also could use it as an rsnapshot server to make backups, but there isn't really a whole lot I need to back up.

My third computer is a Celeron 1.4GHz with 256MB of RAM. Yep, it's junk and I should get rid of it. It's fast enough to run Ubuntu server though, so I could do that. I've been thinking about giving it to my brother for that purpose, but he said he wasn't interested. I could also just scrap it and make use of the Windows XP Professional license and the 20GB hard drive.

Who knows what I'll do.