Mining on your own network, or creating your own mini pool I have one computer set up and solo mining away. The bitcoin client is running in server mode, and bfgminer connects to it with -o 127.0.0.1:8332.

I have a second computer that I'd also like to mine with too, but using the first computer as the server, so that I only need one instance of the blockchain/bitcoin client. Is that possible?

I tried to connect to it with -o 192.168.1.8332, which my router tells me is its network address. But bfgminer fails, saying that I probably got the address wrong.

The firewall is allowing bitcoin-qt.exe through, and I set it to allow port 8332 too, just in case.
I finally sorted this out, so I'm back 17 days later to answer my own question. I also wrote a short article about the steps, should anyone else need them.

Here are the basic steps. The coin is referred to as Coin, as this works with all sha256 coins, and probably (untested by me) Scrypt variants as well. If not, the process will be very similar.

To start, your coin.conf file should look something like this: 

daemon=1
server=1
listen=1
gen=1
rpcuser=uncle_bubs
rpcpassword=your_mother
rpcallowip=127.0.0.1
rpcport=8332



In your coin.conf file, add the line rcpallowip=12.34.56.789, replacing the IP address with the address of the computer you want to allow, or more simply rpcallowip=192.168.1.* to allow any IP address on your network. You can have as many rpcallowip lines as you want. Note that doing this will send your password unencrypted over the network, so it’s not recommended except within a secure network that you control.
Make sure your firewall is allowing incoming connections to coin-qt.exe.
Start coin-qt.exe -server on your server, and give it a moment to get caught up. (You should have the blockchain current before starting).
On your second computer, go into your router’s admin settings and look at the connected devices. This is usually done by entering 192.168.1.1 in a browser. You’ll need the router username and password to get in.
Look for the computer running your server. Mine was 192.168.1.8.
Now add that IP address and computer to the list of reserved addresses. The reason is that even if you leave your computer plugged into the same router all the time, it sometimes shuffles IP addresses unexpectedly. This is normally not a problem, but you need a fixed IP address to connect to. This step ensures your server always has the same IP address.
Finally, start your second miner, using the new address and port obtained from your router settings. Mine was 192.168.1.8:8332.