Arch Linux

timkhuang

Member

Registered: 2021-01-25

Posts: 1

Unstable internet connection on connecting to an external monitor

Thank you for reading this post!

I am running arch on a laptop and everything works fine with the laptop (for now.. May be there is some i haven't discover...). The internet is connected through wifi using NetworkManager. Clash is used for proxy. In terminal, it is used by setting the http_proxy env and https_proxy env. And i changed the /usr/bin/google-chrome-stable content and added a --proxy-server=127.0.0.1:7890 to force every chrome window to use the proxy ( especially for running chrome from dmenu). I am not sure that is the most proper way to achieving that but it works fine now...

The wired problem is, when the laptop is connected to an external monitor, the internet become very slow and sometimes even disconnected. And some website like http://clash.razord.top/ which i think is host locally is also extremely hard to connect... Then, i found out that this problem only occurs when the monitor has switched its source to this laptop. Which means, if the laptop is connected through hdmi and the monitor is currently displaying the content from another computer using USB-C, there is no problem at all, even the laptop still believe it has a second display and can move the workspace to the second screen!

I am not sure what information i need to provide for this problem... But i will post some and please tell me if i have to post more..

here is the result of ping 8.8.8.8 normally:

PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=106 time=289 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=106 time=306 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=106 time=334 ms
64 bytes from 8.8.8.8: icmp_seq=4 ttl=106 time=358 ms

And here is what it looks like when connecting to the external monitor

PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=6 ttl=106 time=1062 ms
64 bytes from 8.8.8.8: icmp_seq=7 ttl=106 time=2054 ms
64 bytes from 8.8.8.8: icmp_seq=8 ttl=106 time=1053 ms
64 bytes from 8.8.8.8: icmp_seq=21 ttl=106 time=270 ms
64 bytes from 8.8.8.8: icmp_seq=23 ttl=106 time=1188 ms

And below are some information that remain unchanged after connecting to the monitor.
this is the result of ip a

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: enp0s31f6: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
    link/ether 54:05:db:ce:f1:df brd ff:ff:ff:ff:ff:ff
3: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 00:42:38:c3:4e:3e brd ff:ff:ff:ff:ff:ff
    inet 192.168.50.124/24 brd 192.168.50.255 scope global dynamic noprefixroute wlp0s20f3
       valid_lft 81989sec preferred_lft 81989sec
    inet6 fe80::377a:c292:c896:8730/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

this is the result of ip r

default via 192.168.50.1 dev wlp0s20f3 proto dhcp metric 600 
192.168.50.0/24 dev wlp0s20f3 proto kernel scope link src 192.168.50.124 metric 600 

this is the content of /etc/resolv.conf

# Generated by NetworkManager
nameserver 192.168.50.1

Thank you for your time! Any help is appreciated!