FAQ for rbldnsd and dnscache

[These notes came from Rick Macdougall of nougen.com on 4 May 2004. Thanks Rick!]

FAQ for rbldnsd and dnscache

Install rbldnsd as per instructions. If you are running FreeBSD you may use the ports collection to do this.
Choose a directory to contain the rbl data you will be downloading or rsyncing from various servers. In our case I choose to use /usr/local/rbldnsd .
Set up and get working your rsync of the data and make sure it works correctly. A working cron job for surbl data is:
```
  {value 0 - 59} * * * *       root /usr/local/scripts/rsyncrbldnsd.sh
```
Where the OS is FreeBSD and you are editing the /etc/crontab file. If you are using crontab -e root, please omit the root word in the above line.
Please replace {value 0 - 59} with a number between 0 and 59, and to minimize the load on the surbl server, try not to use the same number on different servers.
Where rsyncrbldnsd.sh contains:
```
  #!/bin/sh

  /usr/local/bin/rsync -t some_rsync_server::surbl/*.rbldnsd /usr/local/rbldnsd
```
Note: The above is all on one line, and you'll replace some_rsync_server with the actual rsync server name provided when you are granted access. (To get rsync access to the SURBL zone files, please fill out our rsync access form, and let us know the IP address you will be rsyncing from and the approximate number of incoming messages processed per day.)
Get rbldnsd up and running. We run it under daemon tools. Create a new directory in /root (or wherever) called rbldnsd. In the rbldnsd directory, create a file called run with the following information:
```
  #!/bin/sh
  
  exec /usr/local/sbin/rbldnsd -n -l +- -b  \
     ws.surbl.org:dnset:/usr/local/rbldnsd/ws.surbl.org.rbldnsd \
     be.surbl.org:dnset:/usr/local/rbldnsd/be.surbl.org.rbldnsd \
     sc.surbl.org:dnset:/usr/local/rbldnsd/sc.surbl.org.rbldnsd \
```
Save and exit, then make the file executable:
```
  chmod 755 run
```
Then make a subdirectory called log inside /root/rbldnsd and edit a file called run, add the following information to it:
```
  #!/bin/sh
  exec /usr/local/bin/multilog t s5000000 n10 /var/log/rbldnsd
```
Save and exit, then make the shell script executable:
```
  chmod 755 run
```
Now cd to /root
```
  mv rbldnsd /service
```
Your rbldnsd should now start within 5 seconds.
Verify it is running with:
```
  sleep 5; svstat /service/rbldnsd/
```
Get it working with dnscache. Here is the fun stuff:
```
  cd /etc/dnscache/root/servers
  vi be.surbl.org
```
Add your IP that your rbldnsd server is running on to the file. The IP should match the IP added to /service/rbldnsd/run file in step 4
Save and exit.
```
cp be.surbl.org sc.surbl.org
cp be.surbl.org ws.surbl.org

svc -t /service/dnscache 
```
(or restart dnscache if you are not using daemontools).

You should now be running dnscache with it looking at your rbldnsd for the data of be, sc, and ws.surbl.org and looking at the root servers for all other data.

Editor's Notes:

rbldnsd is much faster and more memory efficient than BIND. Therefore you will likely improve your mail processing performance by using rbldnsd to serve all of your RBL zone files. Many RBLs will grant rsync access to rbldnsd versions of their zones by request.
It's no longer necessary to manually reload rbldnsd since by default it will automatically check for and load any changed zone files every 60 seconds. This can be adjusted with the -c command line argument.
Like any name server, log files for rbldnsd queries can get quite large if generated. Be sure to use a log rotation method like the one above or by configuring newsyslog if you choose to keep logs.