Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!lll-crg!topaz!husc6!harvard!rclex!drilex!axiom!linus!raybed2!cvbnet!acrotty From: acrotty@cvbnet.uucp (Art Crotty) Newsgroups: net.unix-wizards Subject: simultaneous file transfer on ethernet (SUN's) Message-ID: <6@cvbnet.uucp> Date: Thu, 21-Aug-86 13:30:10 EDT Article-I.D.: cvbnet.6 Posted: Thu Aug 21 13:30:10 1986 Date-Received: Sun, 24-Aug-86 19:47:46 EDT Organization: Computervision - Netadmin Lines: 99 lineater +3 I have a somewhat complex request for info involving file transfer between hundreds of SUN3 and SUN2 workstations. These workstations' are networked together using ethernet (802.3). Protocols - TCP/IP/UDP. I would like to have the ability to transfer large application programs to all nodes on the network simultaneously. Why I think it may be possible to do this: 1.) The ethernet packet information can contain what is commonly called a multicast bit within the destination address. Thus, I should be able to set this bit to broadcast or spray my large application program (ie. 10mb-30mb) to all nodes on the network. I also, using the multi-cast bit, should be able to set up a table of nodes that I wish to distribute the program to. Thus, if the bit is set to 0 - it is specific address, 1 it is a group of nodes and all 1's in the field indicate all nodes. 2.) Some user-level programs already do something similar to what I want. For instance, "wall" will broadcast a message to nodes on your network. The command "rcp" will copy one or a group of files to one particular destination at a time. I want a "wall" or "rwall" and combined "rcp" that can copy my file or files simultaneously to all nodes or subgroups of nodes on a network. I know NFS allows mounting of an application to nodes and simultaneous access of that application - but that is not what I want. I want to distribute to stand-alone machines as well as file servers new copies of an application once a week and each rcp or "dread the thought" cartridge taping can consume 1/2 hour per node. Thus, 20 nodes is 20 x 1/2 hour by rcp from a master database or less time if multiple tapes are made or rsh tarring from a server with 1/2" tape. I would like to be able to say something like: distribute -g where -g is the option for group and tablefile is the database that contains a list of nodes with names or internet addresses distribute -a where -a is for all nodes - no table I am not that familiar with the networking code on SUN's and was wondering the following: Can it be done? Is this beyond the ability of the Ethernet itself? When "wall" does a broadcast - is it simultaneous to all nodes or consecutive? Will I need some sort of daemon process running, all the time, on each node waiting for a signal to allow broadcast file transmissions, or can /etc/inetd already handle this type of request with little or no code tweeking? What kind of error checking do I have to do for testing that the program was successfully transmitted without losing packets or corrupting packets - at source or destination? Has anyone created a program that can do this? If not, can someone get me started as to the process or code that I might need to access or create to accomplish what I want? For instance: you can alter "inetd" or you have to create a new daemon you must access these libraries and change this/that you must use these calls etc., etc. Thanks in advance for all advice!!! +-------------------------------------------------------------------+ | | | /\ Post: Art Crotty | | / \ Computervision Corp. | | /_ _\ 14 Crosby Drive | | / o o \ Bldg. 5-1 | | -mm--------mm- Bedford, Mass. 01730 | | Ma Bell: (617) 275-1800 | | The fool wanders, UUCP: { decvax,raybed2 }!cvbnet!acrotty | | the wise man travels. | +-------------------------------------------------------------------+