networking - Remove network interface permanently - Ask Ubuntu

i'm trying remove network interface permanently. reason, ifconfig lists eth0 , eth1, although latter rx/tx metrics remain @ zero.

i suspect eth1 entry might causing delays during boot.

surprinsgly, a search did not yield answer on how proceed. posts either older versions of ubuntu or debian, or other distros (redhat), or have no permanent effect, or pertain adding interface, or try turn off after it's been started, or unanswered. answer might somewhere after google's thrid result page.

removing second entry desktop (up , down arrows, on top bar) has no effect either on ifconfig.

edit: actutally have 2 network cards on mb. that's bit of surprise admit. don't have wifi. question still stands, least out of curiosity.

krakoukass@durum:~$ ifconfig eth0      link encap:ethernet  hwaddr 00:1f:d0:a3:40:d9             inet addr:192.168.1.66  bcast:192.168.1.255  mask:255.255.255.0           inet6 addr: fe80::21f:d0ff:fea3:40d9/64 scope:link           broadcast running multicast  mtu:1500  metric:1           rx packets:84 errors:0 dropped:0 overruns:0 frame:0           tx packets:93 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            rx bytes:12255 (12.2 kb)  tx bytes:12241 (12.2 kb)  eth1      link encap:ethernet  hwaddr 00:1f:d0:a3:40:db             broadcast multicast  mtu:1500  metric:1           rx packets:0 errors:0 dropped:0 overruns:0 frame:0           tx packets:0 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            rx bytes:0 (0.0 b)  tx bytes:0 (0.0 b)  lo        link encap:local loopback             inet addr:127.0.0.1  mask:255.0.0.0           inet6 addr: ::1/128 scope:host           loopback running  mtu:65536  metric:1           rx packets:634 errors:0 dropped:0 overruns:0 frame:0           tx packets:634 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:0            rx bytes:64758 (64.7 kb)  tx bytes:64758 (64.7 kb)  krakoukass@durum:~$ lspci | grep -i eth 04:00.0 ethernet controller: realtek semiconductor co., ltd. rtl8111/8168/8411 pci express gigabit ethernet controller (rev 02) 05:00.0 ethernet controller: realtek semiconductor co., ltd. rtl8111/8168/8411 pci express gigabit ethernet controller (rev 02)  krakoukass@durum:~$ cat /etc/network/interfaces # interfaces(5) file used ifup(8) , ifdown(8) auto lo iface lo inet loopback  krakoukas@durum:~$ systemctl -l status ifup@eth1.service ● ifup@eth1.service - ifup eth1    loaded: loaded (/lib/systemd/system/ifup@.service; static; vendor preset: enabled)    active: active (exited) since fri 2015-05-15 12:36:34 cest; 14min ago   process: 457 execstart=/bin/sh -ec ifup --allow=hotplug %i; ifup --allow=auto %i;      if ifquery %i >/dev/null; ifquery --state %i >/dev/null; fi (code=exited, status=0/success)  main pid: 457 (code=exited, status=0/success)  may 15 12:36:34 durum systemd[1]: started ifup eth1. may 15 12:36:34 durum systemd[1]: starting ifup eth1... may 15 12:36:34 durum sh[457]: unknown interface eth1  krakoukas@durum:~$ systemctl -l status ifup@eth0.service ● ifup@eth0.service - ifup eth0    loaded: loaded (/lib/systemd/system/ifup@.service; static; vendor preset: enabled)    active: active (exited) since fri 2015-05-15 12:36:34 cest; 15min ago   process: 458 execstart=/bin/sh -ec ifup --allow=hotplug %i; ifup --allow=auto %i;      if ifquery %i >/dev/null; ifquery --state %i >/dev/null; fi (code=exited, status=0/success)  main pid: 458 (code=exited, status=0/success)  may 15 12:36:34 durum systemd[1]: started ifup eth0. may 15 12:36:34 durum systemd[1]: starting ifup eth0... may 15 12:36:34 durum sh[458]: unknown interface eth0 

thanks in advance help.

open file /etc/network/interfaces in terminal

sudo nano /etc/network/interfaces 

add line:

iface eth1 inet manual 

save file , run

sudo service network-manager restart 

or

sudo systemctl restart network-manager.service 

_source