If statement with multiple conditions

I have a script that runs on multiple servers. What I want to do is have the script do the following:

if $(hostname) is equal to server or server2
 then
   TO_DIR=go
 else
   TO_DIR=stop
fi

I have tried:

if [ ($(hostname) = rphva3011) -o ($(hostname) = rbhtp400) ] 
if [[ $(hostname) = rphva3011 || rbhtp400 ]]

Server is hpux.
any ideas?

start with

if [[ "$server" = "server1" || "$server" = "server2" ]] ; then
   echo ok
else
   echo "not ok"
fi