When a machine is using both a node locked and a floating license, the order that FLEXlm reads the license files depends on the name of the .lic file. FLEXlm reads the license files in alphabetical order, so if you want to make the node locked license to be used first, you can rename the. lic file to start with the letter "A." FLEXlm will search and find that license file first without going out to the server and checking out the floating license.
The server machine should only have the floating .lic file on it so there is no need to do anything with it. The issue just lies on the client machines and you just need to try and force Altia to look at and use the node locked license before searching the server to check out a floating one. You may rename the license files whatever you want, but they must retain the .lic extension.