Every time Linux boots I have to manually use the two commands below in order to have an working internet connection. ethtool -s eth0 autoneg off speed 100 duplex fullifup eth0If I run ethtool eth0 immediately after boot, it describes the problem as Link detected: no.  https://paste.debian.net/hidden/d2b0d461/The same Linux machine receives internet connection after reboot, with no other supplementary commands, if I only change the cable from this router, to my previous DSL router connection (another ISP, but even using the same ethernet cable to the Linux machine).I am looking for a method so the internet connection will start automatically when Lubuntu boots up./etc/network/interfaces: # This file describes the network interfaces available on your system# and how to activate them. For more information, see interfaces(5).source /etc/network/interfaces.d/*# The loopback network interfaceauto loiface lo inet loopback# The primary network interface#auto eth0iface eth0 inet dhcpethtool -s eth0 autoneg off speed 100 duplex fullallow-hotplug eth0#iface wlan0 inet manual#wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf/etc/rc.local: #!/bin/sh -e## rc.local## This script is executed at the end of each multiuser runlevel.# Make sure that the script will exit 0 on success or any other# value on error.## In order to enable or disable this script just change the execution# bits.## By default this script does nothing.echo 500 > /sys/class/backlight/intel_backlight/brightnessxrandr -s 960x540rfkill block bluetoothrfkill block wifiethtool -s eth0 autoneg off speed 100 duplex fullip link set eth0 upifup eth0dhcpcd eth0exit 0systemctl status rc-local: globalisation@WindowsXP:~$ systemctl status rc-local rc-local.service - /etc/rc.local Compatibility   Loaded: loaded (/lib/systemd/system/rc-local.service; static; vendor preset:   Drop-In: /lib/systemd/system/rc-local.service.d           debian.conf   Active: failed (Result: exit-code) since Sun 2017-06-04 00:31:28 CEST; 15min   Process: 636 ExecStart=/etc/rc.local start (code=exited, status=1/FAILURE)Jun 04 00:31:27 WindowsXP systemd[1]: Starting /etc/rc.local Compatibility...Jun 04 00:31:28 WindowsXP rc.local[636]: Can't open displayJun 04 00:31:28 WindowsXP systemd[1]: rc-local.service: Control process exited, Jun 04 00:31:28 WindowsXP systemd[1]: Failed to start /etc/rc.local CompatibilitJun 04 00:31:28 WindowsXP systemd[1]: rc-local.service: Unit entered failed statJun 04 00:31:28 WindowsXP systemd[1]: rc-local.service: Failed with result 'exitglobalisation@WindowsXP:~$When Lubuntu boots it appears these errors:Failed to start LSB: IPV4 DHCP client with IPV4ALL support. See 'systemctl status dhcpcd.service' for details 16.780656 usb 1-1.4.3: device descriptor read/64, error -110/etc/sysctl.conf: ## /etc/sysctl.conf - Configuration file for setting system variables# See /etc/sysctl.d/ for additional system variables.# See sysctl.conf (5) for information.##kernel.domainname = example.com# Uncomment the following to stop low-level messages on console#kernel.printk = 3 4 1 3##############################################################3# Functions previously found in netbase## Uncomment the next two lines to enable Spoof protection (reverse-path filter)# Turn on Source Address Verification in all interfaces to# prevent some spoofing attacks#net.ipv4.conf.default.rp_filter=1#net.ipv4.conf.all.rp_filter=1# Uncomment the next line to enable TCP/IP SYN cookies# See http://lwn.net/Articles/277146/# Note: This may impact IPv6 TCP sessions too#net.ipv4.tcp_syncookies=1# Uncomment the next line to enable packet forwarding for IPv4#net.ipv4.ip_forward=1# Uncomment the next line to enable packet forwarding for IPv6#  Enabling this option disables Stateless Address Autoconfiguration#  based on Router Advertisements for this host#net.ipv6.conf.all.forwarding=1#################################################################### Additional settings - these settings can improve the network# security of the host and prevent against some network attacks# including spoofing attacks and man in the middle attacks through# redirection. Some network environments, however, require that these# settings are disabled so review and enable them as needed.## Do not accept ICMP redirects (prevent MITM attacks)#net.ipv4.conf.all.accept_redirects = 0#net.ipv6.conf.all.accept_redirects = 0# _or_# Accept ICMP redirects only for gateways listed in our default# gateway list (enabled by default)# net.ipv4.conf.all.secure_redirects = 1## Do not send ICMP redirects (we are not a router)#net.ipv4.conf.all.send_redirects = 0## Do not accept IP source route packets (we are not a router)#net.ipv4.conf.all.accept_source_route = 0#net.ipv6.conf.all.accept_source_route = 0## Log Martian Packets#net.ipv4.conf.all.log_martians = 1#net.ipv6.conf.all.disable_ipv6 = 1net.ipv6.conf.default.disable_ipv6 = 1net.ipv6.conf.lo.disable_ipv6 = 1If you have please any ideas how this could happen, I have just remembered that  this in discussion same machine + same OS(Linux no changed configurations) + same Ethernet cable always received and kept  the internet automatically (no extra manual commands) from all the 3 different models of routers. All 3 connections and routers were from the same ISP, other than this forth problematic connection and router. Best wishes.
How to get internet connection starting automatically, without manually running `ethtool` every time
networking;lubuntu