eth0 changed to eth1 or eth2 and the solution to fix it

If you move your hard drive(s) around to other computers/servers, you'll find that your eth0 keeps getting higher, the first time it will become eth1 and then eth2 etc and even higher if your server has dual or quad NICs.  The reason is that udevd basically assigns eth0 tot he first NIC it finds and remembers it, if it encounters a NIC with a different MAC, it assigns it one higher (eg. eth1).

See the example below, I have eth2 now so how do I fix it?

ifconfig
eth2      Link encap:Ethernet  HWaddr 90:e6:ba:30:fb:0c 
          inet addr:192.168.1.103  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::92e6:baff:fe30:fb0c/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:62000457 errors:0 dropped:0 overruns:0 frame:0
          TX packets:25890816 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:3247729393 (3.2 GB)  TX bytes:1775390659 (1.7 GB)
          Interrupt:253 Base address:0xa000




vi /etc/udev/rules.d/70-persistent-net.rules


# This file maintains persistent names for network interfaces.
# See udev(7) for syntax.
#
# Entries are automatically added by the 75-persistent-net-generator.rules
# file; however you are also free to add your own entries.

# PCI device 0x10de:0x03ef (forcedeth)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:19:66:51:42:83", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"

# PCI device 0x10ec:0x8168 (r8169)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="20:cf:30:79:a4:95", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"

# PCI device 0x10ec:0x8168 (r8169)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="90:e6:ba:30:fb:0c", ATTR{type}=="1", KERNEL=="eth*", NAME="eth2"

 

Remove the two entries at the top and then change the last entry where it says "eth2" to "eth0" and reboot your computer. 

I thought restarting udevd and network/networking would enable it on the fly but it doesn't, I believe this is because Linux assigns a static device name at boot time only.

 


Tags:

eth, itif, servers, ll, etc, server, dual, quad, nics, udevd, assigns, tot, nic, encounters, eg, ifconfig, encap, ethernet, hwaddr, fb, inet, addr, bcast, fe, baff, scope, broadcast, multicast, mtu, metric, rx, packets, errors, overruns, tx, carrier, collisions, txqueuelen, bytes, gb, xa, vi, udev, persistent, maintains, interfaces, syntax, entries, automatically, generator, pci, ef, forcedeth, subsystem, quot, drivers, attr, kernel, ec, cf, entry, reboot, restarting, networking, enable, doesn, linux, static,

Latest Articles

  • Aruba/HP/Dell IAP Wireless Controller Common Default Passwords
  • Debian, Mint Ubuntu how to remove package and associated config files
  • Linux Grub not booting the intended kernel solution in Debian, Mint, Ubuntu how to specify which kernel to boot by default
  • QEMU KVM Keyboard Problems Not Working Right Repeating Characters, Ctrl+C Copy and Paste not working right when using PS2 mouse in guests Solution
  • Linux how to compile binary with static sharedobjects embedded instead of dynamic to use on multi-distributions and avoid glibc compatiblity issues
  • /bin/sh: msgfmt: not found error solution on Linux Compilation Ubuntu Debian Mint Centos
  • Mikrotik RouterOS CHR/ISO Basic and Quick Setup Howto Guide
  • qemu 4 compilation options
  • CentOS 7 8 PXEBoot Netinstall Not Working Solution "Pane is dead "new value non-exisetnt xfs filesystem is not valid as a default fs type"
  • CentOS 6 EOL yum repo won't work Error: Cannot find a valid baseurl for repo: base Solution
  • CentOS 7 8 How To Disable SELinux
  • Wordpress How To Add Featured Image To Post in Hueman Theme
  • kdenlive full reset how to erase all config files
  • CentOS 7 8 yum error Trying other mirror. To address this issue please refer to the below wiki article
  • Microsoft Teams Linux - Calendar Doesn't Work Missed Meetings!
  • Scanner not working in Linux Ubuntu Fedora Mint Debian over the network? Use sane-airscan!
  • How To Boot, Install and Run Windows 2000 on QEMU-KVM
  • bash cannot execute permission denied
  • Huion and Wacom Tablets How To Install in Linux Mint / Ubuntu and make the stylus work properly
  • ffmpeg how to cut certain parts of video out