Hi, I just installed the 2.4.20 kernel on my GNU/Debian box (emachine 333 w/ Etherlink III card). It is connected to a T1 via DHCP but after installing the kernel (I did include the Etherlink III driver) and rebooting I have no net access. Did I miss some super-duper important module or do I have to do something to get DHCP working again? Thanks in advance for any help with this..

FYI: I followed these instructions very closely but used make menuconfig since I couldn't get make xconfig working for some reason..

http://www.osnews.com/story.php?news_id=2949

Not sure about Debian specifically, but the /etc/sysconfig/network-scripts/ifcfg-eth0 file is the central location for configuring interfaces for RedHat... Should contain the following for a DHCP-enabled interface:
DEVICE=eth0
BOOTPROTO=dhcp
ONBOOT=yes
(I'm hoping you have a similar file on your system)

Looks like the file in Debian is /etc/network/interfaces.. and it's correct:

# The loopback interface
auto lo
iface lo inet loopback

# The first network card -this entry was created during Debian installation
auto eth0
iface eth0 inet dhcp

This is frustrating b/c is the 3rd time I've done this without success... any other ideas?

A 3Com Etherlink III, if I remember correctly is a 3c509 card. If you are using kernel modules, the module name should be 3c509.o... is this module showing up with lsmod? What does /etc/modules.conf look like? It should contain a line reading 'alias eth0 3c509'. Or, did you recompile your kernel to include support for this?

lsmod doesn't show anything and there is no alias eth0 at all in the etc/modules.conf. I did not install the card with a <M> but rather I fully installed it <*>. Here is the results of my dmesg if it helps:

Linux version 2.4.20 (root@goldmoon) (gcc version 2.95.4 20011002 (Debian prerelease)) #1 SMP Mon Mar 31 20:55:41 EST 2003
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 000000000009fc00 (usable)
BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 0000000004000000 (usable)
BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved)
BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
BIOS-e820: 00000000fffc0000 - 0000000010000000 (reserved)
64MB LOWMEM available
On node - totalpages: 16384
zone(0): 4096 pages.
zone(1): 12288 pages.
zone(2): 0 pages.
Kernel command line: auto BOOT_IMAGE=Linux ro root=302
No local APIC present or hardware disabled
Initializing CPU#0
Detected 250.061 Mhz processor.
Console: colour VGA+ 80x25.
Calibrating delay loop... 498.07 BotoMIPS
Memory: 61344k/65536k available (1749 kernel code, 3804k reserved, 722k data, 1 32k init, 0k highmem)
Checking if this processor honours the WP bit even in supervisor mode...Ok.
Dentry cache hash table entries: 8192 (order: 4, 65536 bytes)
Inode cache hash table entries: 4096 (order: 3, 32768 bytes)
Mount-cache hash table entries: 1024 (order: 1, 8192 bytes)
Buffer-cache hash table entries: 4096 (order:2, 16384 bytes)
Page-cache hash table entries: 16384 (order: 4, 65536 bytes)
CPU: After generic, caps: 0080a135 00000000 00000000 00000004
CPU Common caps: 0080a135 00000000 00000000 00000004
Checking 'hlt' instruction... OK.
Checking for popad bug... OK.
POSIX conformance testing by UNIFIX
CPU: After generic, caps: 0080a135 00000000 00000000 00000004
CPU Common caps: 0080a135 00000000 00000000 00000004
CPU0: Cyrix M II 3x Core/Bus Clock stepping 08
per-CPU timeslice cutoff: 159.90 usecs.
SMP motherboard not detected.
Local APIC not detected. Using dummy APIC emulation
Waiting on wait_init_idle (map = 0x0)
All processors have done init_idle
PCI: PCI BIOS revision 2.10 entry at 0xfdb31, last bus=1
PCI: Using configuration type 1
PCI: Probing PCI hardware
PCI: Using IRQ router VIA [1106/0596] at 00:07.0
Activating ISA DMA hang workarounds.
ispnp: Scanning for PnP cards...
isapnp: Card 'Crystal CS4235'
ispnp: Card '3Com 3C509B EtherLink III'
isapnp: 2 Plug & Play cards detected total
Linux NET4.0 for Linux 2.4
Based upon Swansea University Computer Society NET3.039
Initializing RT netlink socket
Starting kswapd
Jouralled block Device driver loaded
Installing knfsd (copyright (C) 1996 okira@monad.swb.de).
NTFS driver v1.1.22 [Flags: R/O]
parport0: PC-style at 0x378 (0x778) [PCSPP(,...)]
parport0: irq 7 detected
pty: 256 Unix98 ptys configured
Serial driver version 5.05c (2001-07-08) with MANY_PORTS SHARE_IRQ_SERIAL_PCI IS APNP enabled
ttyS00 at 0x03f8 (irq=4) is 16550A
Uniform Multi-Platform E-IDE driver Revision: 6.31
ide: Assuming 33Mhz system bus speed for PIO modes; override with idebus=xx
VP_IDE: IDE controller on PCI bus 00 dev 39
VP_IDE: detected chipset, but driver not compiled in!
VP_IDE: chipset revision 6
VP_IDE: not 100% native mode: will probe irqs later
ide0: BM-DMA at 0xffa0-0xffa7, BIOS settings: hdaMA, hdbio
ide1: BM-DMA at 0ffa8-0xffaf, BIOS settings: hdcMA, hddio
hda: SAMSUNG SV0322A, ATA DISK drive
hdc: SAMSUNG SCR-2432, ATAPI CD/DVD-ROM drive
ide0 at 01f0-0x1f7,0x3f6 on irq14
ide1 at 0x170-0x177,0x376 on irq 15
hda: 6250608 sectors (3200MB) w/478KiB Cache, CHS=775/128/63
hdc: ATAPI 32X CD-ROM drive, 128kB Cache
Uniform CD-ROM driver Revision: 3.12
Partition check:
hda: hda1 hda2 hda3
Floppy drives: fd0 is 1.44M
FDC - is a post-1991 82077
eth0: 3c5x9 at 0x220, 10baseT port, address 00 a0 24 05 20 4d, IRQ5
3c509.c:1.19 160ct2002 becker@scyld.com
http://www.scyld.com/network/3c509.html
Linux agpgart interface v.0.99 (c) Jeff Hartmann
agpgart: Maximum main memory to use for agp memory: 28M
agpgart: Detected Via MVP3 chipset
agpgart: AGP aperture is 64M @0xf8000000
[drm] AGP 0.99 on VIA MVP3 @ 0xf8000000 64MB
[drm] Initialized i810 1.2.0 20010920 on minor 0
SCSI subsystem driver Revision: 1.00
es1371: version v0.30 time 21:03:05 Mar 31 2003
sc4281: version v1.30.32 time 21:02:49 Mar 31 2003
usb.c: registered new driver hub
uhci.c: USB Universal Host Controller Interface driver v1.1
PCI: Found IRQ11 for device 00:07.2
uhci.c: USB UHCI at I/O 0xea00, IRQ 11
usb.c: new USB bus registered, assigned bus number 1
hub.c: USB hub found
hub.c: 2 ports detected
usb.c: registered new driver usbscanner
scanner.c: 0.4.6:USB Scanner Driver
usb.c: registered new driver usblp
printer.c: v0.11: SUB Printer Device Class driver
usb.c: registered new driver dc2xx
dc2xx.c: v1.0.0:USB Camera Driver for Koda DC-2xx series cameras
Initiazling USB Mass Storage driver...
usb.c: Mass Storage support registered.
NET4: Linux TCP/IP 1.0 for NET4.0
IP Protocols: ICMP, UDP, TCP, IGMP
IP: routing cache hash table of 512 buckets, 4kbytes
TCP: Has tables configured (established 4096 bind 4096)
NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
NET4: Linux IPX 0.47 for NET4.0
IPX Portions Copyright (c) 1995 Caldera, Inc.
IPX Poritons Copyright (c) 2000, 2001 Conectiva, Inc.
VFS: Mounted root (ext2 filesystem) readonly.
Freeing unused kernel memory: 132k freed
Adding Swap: 197560k swap-space (priority -1)
eth0: Setting 3c5x9/3c5x9B half-duplex mode if_port: 0, sw)info: 1311

Okay - turns out the answer is that I needed to include socket filtering in the kernel. Didn't seem that way from the help screen but that's the way it goes. Socket Filtering required for DHCP.

Google is my friend. I had the same problem, and ended up here after a search. The same solution worked for me, so now my Debian unstable with custom kernel 2.4.20 is up and running again. Thanks!