This is part of The Pile, a partial archive of some open source mailing lists and newsgroups.
Subject: Extra Machine-to-machine ethernet connection? From: getrhd@terrorist.math.ntu.edu.tw Date: Wed, 31 Mar 1999 23:33:27 +0800 Hello, ladies and gentlemen: I am running Red Hat on two dual PII machines. Currently they sit side-by-side, both connected to a 10BaseT LAN network (well, it's not a rich department!). I am thinking about using NFS on the larger (better-equipped) of the two machines and mount some directories. I'm also transferring files between the two machines constantly. Unlucky, since the 10BaseT LAN does not seem very well equipped to take such a load. I have a spare 3C905B 10/100 NIC, and am thinking of buying an extra 10/100 NIC and making a machine-to-machine direct connection. What equipment do I need? I know there is something called a Null Modem Cable that I can use for a direct socket-to-socket 10 Mb/s connection between two 10Mbps NICs. Is it doable for 100Mb/s? Would a simple 10 Mb/s connection suffice if I am running PVM? ======= Subject: Re: Extra Machine-to-machine ethernet connection? From: djb@chef.redhat.com (Donnie Barnes) Date: 31 Mar 1999 16:25:29 GMT > I am running Red Hat on two dual PII machines. Currently they >sit side-by-side, both connected to a 10BaseT LAN network (well, it's >not a rich department!). I am thinking about using NFS on the larger >(better-equipped) of the two machines and mount some directories. I'm >also transferring files between the two machines constantly. Unlucky, >since the 10BaseT LAN does not seem very well equipped to take such a >load. I have a spare 3C905B 10/100 NIC, and am thinking of buying an >extra 10/100 NIC and making a machine-to-machine direct connection. > > What equipment do I need? I know there is something called a >Null Modem Cable that I can use for a direct socket-to-socket 10 Mb/s >connection between two 10Mbps NICs. Is it doable for 100Mb/s? Would >a simple 10 Mb/s connection suffice if I am running PVM? You want to make (or get) a CAT5 crossover cable. You should be able to find the pin-outs on the 'net somewhere for how to make one yourself, but it will probably require an RJ-45 crimper, a couple heads, and a cable. You can likely buy them as well. Then plug the two NIC's into the machines, plug the cable in, and configure them for private networking. That said, NFS won't really be noticeably faster, I don't think. It will for 2.2 kernel based systems running knfsd, but probably not for 2.0 based systems. The NFS server on 2.0 based Linux can't fill a 10Mbs pipe, let alone a 100Mbs pipe. Now, *if* your 10Mbs network is very congested already, then this private network will still help. ======= Subject: Re: Extra Machine-to-machine ethernet connection? From: Tim Pickering <tim@astro.rug.nl> Date: Wed, 31 Mar 1999 19:02:15 +0200 > That said, NFS won't really be noticeably faster, I don't think. It > will for 2.2 kernel based systems running knfsd, but probably not for > 2.0 based systems. The NFS server on 2.0 based Linux can't fill a > 10Mbs pipe, let alone a 100Mbs pipe. Now, *if* your 10Mbs network is > very congested already, then this private network will still help. using the user-land nfsd and 2.2.1 on my P5-100 at work i can get 2--3 MB/sec transfers between it and my ultra 10. they're each running half-duplex 100 Mb/s and are on the same switch. i don't have numbers for nfsd with a 2.0.x kernel on the same hardware, though. considering my main drive on the P5 only gets 3.5--4 MB/sec locally, 2--3 MB/sec ain't bad. thus, you can indeed fill a 10 Mb/s pipe with 2.2.x with either knfsd or plain nfsd. this may be a FAQ somewhere, but is it possible to full duplex with a crossover cable only or is a hub required? if so, that might be another win for doing the private network. ======== Subject: Re: Extra Machine-to-machine ethernet connection? From: Bruce Tong <zztong@laxmi.ev.net> Date: Wed, 31 Mar 1999 12:07:16 -0500 (EST) > > That said, NFS won't really be noticeably faster, I don't think. It > > will for 2.2 kernel based systems running knfsd, but probably not for > > 2.0 based systems. The NFS server on 2.0 based Linux can't fill a > > 10Mbs pipe, let alone a 100Mbs pipe. Now, *if* your 10Mbs network is > > very congested already, then this private network will still help. > > using the user-land nfsd and 2.2.1 on my P5-100 at work i can get 2--3 > MB/sec transfers between it and my ultra 10. they're each running > half-duplex 100 Mb/s and are on the same switch. i don't have numbers > for nfsd with a 2.0.x kernel on the same hardware, though. > considering my main drive on the P5 only gets 3.5--4 MB/sec locally, > 2--3 MB/sec ain't bad. thus, you can indeed fill a 10 Mb/s pipe with > 2.2.x with either knfsd or plain nfsd. I've no experience with SLIP/PPP connections over a null modem serial cable, but that would be a pretty inexpensive solution. Would he be able to approach those ethernet data rates that way? I'm guessing the answer is no, but I thought I'd mention it just in case we're overlooking an obvious solution. =========== Subject: Re: Extra Machine-to-machine ethernet connection? From: John Summerfield <summer@OS2.ami.com.au> Date: Thu, 1 Apr 1999 01:13:56 +0800 (WST) On Wed, 31 Mar 1999, Tim Pickering wrote: > this may be a FAQ somewhere, but is it possible to full duplex with > a crossover cable only or is a hub required? if so, that might be I have a crossed over cable. Let the epic drive speak for itself: epic100.c:v1.04 8/23/98 Donald Becker http://cesdis.gsfc.nasa.gov/linux/drivers/epic100.html eth1: SMC EPIC/100 at 0xb800, IRQ 9, 00:e0:29:07:13:95. eth1: MII transceiver #3 control 3000 status 7809. eth1: Autonegotiation advertising 01e1 link partner 0001. eth1: Setting full-duplex based on MII #3 link partner capability of 41e1. and the other one: eth0: SMC EPIC/100 at 0xb800, IRQ 10, 00:e0:29:07:3b:1b. eth0: MII transceiver #3 control 3000 status 7809. eth0: Autonegotiation advertising 01e1 link partner 0001. Partition check: sda: sda1 hda: hda1 hda2 hda3 hda4 < hda5 hda6 hda7 hda8 hda9 > hdb: hdb1 < hdb5 hdb6 hdb7 hdb8 > hdc: hdc1 < hdc5 hdc6 hdc7 > NTFS version 990102 VFS: Mounted root (ext2 filesystem) readonly. Freeing unused kernel memory: 52k freed Adding Swap: 128484k swap-space (priority -1) Soundblaster audio driver Copyright (C) by Hannu Savolainen 1993-1996 SB 3.1 detected OK (220) YM3812 and OPL-3 driver Copyright (C) by Hannu Savolainen, Rob Hooft 1993-1996 eth0: Setting full-duplex based on MII #3 link partner capability of 41e1. The first is a module: I had a problem getting two nics working with the drivers compiled in. The second is compiled in: hence its messages are mixed with others. ========= Subject: Re: Extra Machine-to-machine ethernet connection? From: Tim Pickering <tim@astro.rug.nl> Date: Wed, 31 Mar 1999 19:20:50 +0200 > I've no experience with SLIP/PPP connections over a null modem serial > cable, but that would be a pretty inexpensive solution. Would he be able > to approach those ethernet data rates that way? I'm guessing the answer > is no, but I thought I'd mention it just in case we're overlooking an > obvious solution. null modem links are limited by the speed of the serial port which is usually 115 kbaud and still significantly slower than even 10 Mb/s ethernet. if you already have the NICs, crossover cables are pretty cheap and relatively easy to find. i think I've seen them at best buy. even if you don't have the NICs, brand new tulip-based 10/100 cards are $25 so for $50-60 you can have your machines talk at 100 Mb/s with very little cpu overhead. i like my tulip cards :) i wish my laptop had one. ============ Subject: Re: Extra Machine-to-machine ethernet connection? From: John Summerfield <summer@OS2.ami.com.au> Date: Thu, 1 Apr 1999 01:24:32 +0800 (WST) On Wed, 31 Mar 1999, Bruce Tong wrote: > I've no experience with SLIP/PPP connections over a null modem serial > cable, but that would be a pretty inexpensive solution. Would he be able > to approach those ethernet data rates that way? I'm guessing the answer > is no, but I thought I'd mention it just in case we're overlooking an > obvious solution. A serial port in training can achieve about 115 000 bits/sec. A 10-base NIC is supposed to reach 10 000 000 bits/sec. A 100-base NIC is supposed to reach 100 000 000 bits/sec.