Put all of your command line arguments towards the beginning with the pool at the end. The just put a space and start your next pool another -o set of parameters. Add as many pools and/or servers as you want.
Hello: I tried this, but I did it wrong. What do I need to correct?
cgminer-3.1.1-windows\cgminer.exe --scrypt -I 20,20,20,20 -o -u xxx.1 -p x --thread-concurrency 22400 --gpu-threads 1 --worksize 256 --lookup-gap 2 --gpu-engine 905,905,905,905 --gpu-memclock 1250,1250,1250,1250 --auto-fan --config C:\xxx\x\x\cgminer-3.1.1-windows\cgminer.conf stratum+tcp://us-west.multipool.us:3352 -o stratum+tcp://us-east.multipool.us:3352 -u xx.1 -p x --thread-concurrency 22400 --gpu-threads 1 --worksize 256 --lookup-gap 2 --gpu-engine 905,905,905,905 --gpu-memclock 1250,1250,1250,1250 --auto-fan --config C:\x\x\x\cgminer-3.1.1-windows\cgminer.conf
Uh, OK, Lets go back to your original post's command line
cgminer.exe --scrypt -I 20,20,20,20 -o stratum+tcp://us-west.multipool.us:3352 -u XXX.1 -p XX --thread-concurrency 22400 --gpu-threads 1 --worksize 256 --lookup-gap 2 --gpu-engine 905,905,905,905 --gpu-memclock 1250,1250,1250,1250 --auto-fan --config C:\XXX\xxx\xxx\cgminer-3.1.1-windows\cgminer.conf
I would change it to
cgminer.exe --scrypt -I 20,20,20,20 --thread-concurrency 22400 --gpu-threads 1 --worksize 256 --lookup-gap 2 --gpu-engine 905,905,905,905 --gpu-memclock 1250,1250,1250,1250 --auto-fan --config C:\XXX\xxx\xxx\cgminer-3.1.1-windows\cgminer.conf -o stratum+tcp://us-west.multipool.us:3352 -u XXX.1 -p XX -o "failover pool stuff here"
I've never used the .conf file so I don't know what the ramifications are with combining that with command line options. I would recommend using one or the other and not both.
Sam