tedcrane@batcomputer.tn.cornell.edu (Ted Crane) (04/20/87)
A while back, I put a request for methods of identifying VAXes into an article in mod.computers.vax. As promised, here is a summary of the responses: 1) Don't do it. Just about everyone who responded fervently denounced the idea of checking for a VAX system ID number as a means of protecting programs from unauthorized copying. The reasons are many (especially on a VAX) and are listed below. One honest soul even went so far as to point out that VAX (presumably VMS) owners are of the temperament to spend $$$ for reliable software, and shouldn't be expected to make copies. 2) It can't be done. VAXes have no useful serial number on the CPU. There's a rumor that the 2000's have a serial number on the CPU board, but it is suject to the same problem as the Ethernet ID, below. Various software manufacturers who are checking the system serial number via GETSYI are probably fooling themselves (or they know something we don't). 3) Don't use the Ethernet physical address as an ID. Some VAXes don't have Ethernet boards. The ID changes when field service swaps the board. (This is not exactly true, since they can easily preserve the ID by moving a socketed ROM). 4) Don't use a disk serial number as an ID. VAX managers are fond of swapping system disks (does it make sense to check the ID of any other disk?). Field service also likes to swap HDA's and drives. I think the casual reader of this summary will have gotten the idea by now. While I am still interested in finding a way to do it (can anyone suggest how to read a disk serial number? There is a VCB$W_VOLSER you can see in ANAL/SYS, but it is always zero!), the chance of incorrectly breaking someones software is too high. <Facts reported above may not really be correct, so don't use them without researching them yourself...> -- - ted crane, alias (tc) tedcrane@tcgould.tn.cornell.edu BITNET: tedcrane@CRNLTHRY tedcrane@squid.tn.cornell.edu DECnet: GOPHER::THC