Multiple Remote Copy

Tactix ReEngineering Inc’s Multiple Remote Copy (MRCP) is one of those applications that you wonder how you managed to get along without only after you’ve used it for a while. The concept of MRCP is simple: perform a broadcast of software to multiple target machines in one single push. It doesn’t matter what operating system you are dealing with or even what type of network, the medium the use, or the size of the files. MRCP will send a broadcast to all UNIX clients and confirm the acceptance from each client. To add to the utility, MRCP even include network bandwidth minimization routines.

Although you might be unsure about the utility of such a tool, imagine a few examples where MRCP can help out on your network. You need to update each of your clients with the latest anti-virus definition file. You need to send current pricing information, or you might need to share a corporate-wide document. Or you might need to send out a whole new application to end users. The old way to do this was to either walk around to each machine with diskettes or CD in hand and load manually. More sophisticated networks let you walk to each client and load off a server. But with MRCP you need only sit at the console of the server and instruct the tool to broadcast to clients. Simple, fast, and a lot less sneaker wear.

MRCP is available for a variety of operating systems. We were supplied with both SCO UnixWare 7 and OpenDesktop versions, and used it on both types of servers broadcasting to a network of twelve UNIX workstations. Our network runs TCP/IP over a mix of 10 and 100Mbps Ethernet cards, as well as two wireless links. Loading the MRCP software is simple: mount the CD-ROM and run an installation script. A menu asks for the proper hardware and software combination to load, as well as whether the machine is a server or not. A client package must be installed on each machine which could conceivably receive updates from the server. Each client runs a daemon which consumes minimal resources. Unfortunately there is no Windows 95 client (although Windows NT is supported), although one should eventually appear. You can mix clients any way you want, as long as the client software is available for it.

The interface to MRCP is command-line only, which is too bad as an X interface would have been nice. The format of the command to start MRCP is simple: you specify the list of clients, the source file name, and the destination file name. The entire process can be scripted for batching or cron execution. When a copy command is sent, each client’s daemon responds to a poll from the MRCP server and after the list of clients is established, a single broadcast of the files is conducted. Finally, the server polls each client to confirm full reception and any problems corrected.

We tested MRCP over a week-long session with automated broadcasts of several large documents and databases each night. In each case, every file was transferred properly with nary a hitch. To check loading of the network, we broadcast a set of five 40MB databases during working hours, and while there was some slow-down in the network it was manageable and lower than we had expected. Obviously MRCP does a good job of handling bandwidth optimization. If you have to update clients with identical files at intervals, MRCP is one of the slickest ways to do it.