Ubuntu Support Template
Ubuntu Version:
24.04 LTS
Desktop Environment (if applicable):
XFCE
Problem Description:
Every now and then my wired (!) internet access breaks. I can’t surf the internet or install packages via my package manager. But I CAN ping google.com.
The thing that helps is logging out and in. So nothing wrong w/ my hardware.
Relevant System Information:
Stopping my VPN (PIA) doesn’t help either.
What I’ve Tried:
Logging out and in: works.
When you connect to PIA (VPN) it changes your current DNS to their DNS. When you disconnect from PIA, it should revert back to your original setting. There is a file, /etc/openvpn/update-resolv-conf and the first few lines say that you need to add in your .ovpn
script-security 2
up /etc/openvpn/update-resolv-conf
down /etc/openvpn/update-resolv-conf
resolvectl before vpn
Current DNS Server: 10.0.0.1
resolvectl after connect vpn
Current DNS Server: 192.168.1.1
resolvectl after disconnect vpn
Current DNS Server: 10.0.0.1
Your IP numbers will be different but you get the idea.
I would start with nslookup and traceroute command line tools.
The first will indicate if dns lookups (mapping site name to ip address) is working; the second will indiate if route to those sites is having issues.
Thanks for those tips. Will do the next time I’m disconnected from the internet.
Have any of you an idea why the problem is gone after a re-login? Are certain services stopped if you don’t use ‘m for a long time?
Can you ping 8.8.8.8 when the ping fails?
Usually all user services are stopped, unless explicitly set otherwise, giving you a clean slate when logging back in, so that’s at least a clue. System services may shutdown when unused, there is a systemd setting for that, but I cannot say I’ve seen it being used. You can search for service units that have StopWhenUnneeded=:
sudo grep -ir StopWhenUnneeded= /{etc,run,usr/lib}/systemd
This needs sudo because /run/systemd may be inaccessible otherwise. You should also not search for yes, because that is not the only name for Boolean yes/no values in systemd.
Please use code blocks (</>) around all logs and other console/terminal output, ideally wrapped in a “Hide Details” element. See items 4 and 5 in the Posting Guide.
If you are so inclined, I took it upon myself to provide a little helper script for that.
Thank you for the help/hints. This is the output of the command:
/usr/lib/systemd/user/bluetooth.target:StopWhenUnneeded=yes
/usr/lib/systemd/user/printer.target:StopWhenUnneeded=yes
/usr/lib/systemd/user/graphical-session-pre.target:StopWhenUnneeded=yes
/usr/lib/systemd/user/graphical-session.target:StopWhenUnneeded=yes
/usr/lib/systemd/user/sound.target:StopWhenUnneeded=yes
/usr/lib/systemd/user/xdg-desktop-autostart.target:StopWhenUnneeded=yes
/usr/lib/systemd/user/smartcard.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/bluetooth.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/printer.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/blockdev@.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/brltty-udev.service:StopWhenUnneeded=true
/usr/lib/systemd/system/hybrid-sleep.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/sleep.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/suspend.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/systemd-journald@.socket:StopWhenUnneeded=yes
/usr/lib/systemd/system/hibernate.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/systemd-journald-varlink@.socket:StopWhenUnneeded=yes
/usr/lib/systemd/system/sound.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/suspend-then-hibernate.target:StopWhenUnneeded=yes
/usr/lib/systemd/system/user-.slice.d/10-defaults.conf:StopWhenUnneeded=yes
/usr/lib/systemd/system/user-runtime-dir@.service:StopWhenUnneeded=yes
/usr/lib/systemd/system/smartcard.target:StopWhenUnneeded=yes
Looks to me like there’s no network/internet service in that list…
Yes, indeed, that’s pretty much what I am getting on my end. I think we can cross that off the list.
I don’t use PIA, or any VPN for that matter, so I can only give you more general advice on debugging network issues.
Can you tell us some more about how the error manifests? @pavlos’ suggestion seems to go in the right direction. It could be a DNS issue. That you can still ping google.com may be misleading, because that’s most likely in the DNS resolver’s cache. Next time this happens, you could do a ping first, to see if it’s still the same. Then flush the DNS cache and try again, it it doesn’t work anymore, it’s a DNS issue.
The somewhat tricky part is to figure out, what your resolver is, to reliably flush the correct cache. On a standard Ubuntu Desktop it should be systemd-resolved.
resolvectl status
should show if that’s the case and if so:
resolvectl flush-caches
will clear the DNS cache.
To add to @matt-rw’s suggestion. You can check the routing table of your machine with this
ip route
Ideally, you do a “before” snapshot, i.e. when it’s working alright, so we can compare it to “after”, when the failure happens.
But the route is only half the story, so here is the other one:
ip address
A before/after will go a long way here too.
@pavlos You wrote:
"
When you connect to PIA (VPN) it changes your current DNS to their DNS. When you disconnect from PIA, it should revert back to your original setting. There is a file, /etc/openvpn/update-resolv-conf and the first few lines say that you need to add in your .ovpn
script-security 2
up /etc/openvpn/update-resolv-conf
down /etc/openvpn/update-resolv-conf
"
I disabled Snap and maybe that uninstalled certain stuff.
If I do a system wide find on my system then I can not find anything with “ovpn” or “update-resolv-conf” in the name. As you know I use a VPN from PIA (Private Internet Access): is it safe - or even a good idea - to install the package ‘openvpn’ via my package manager? Or will that “bite” my PIA VPN?
@peterwhite23 Thank you for the tips and the “redirection” to Pavlos’ reply. Next time if I lose internet connection I’ll flush the DNS cache before doing a ping. Good tip!
user@u24:~$ sudo find / -name "update-resolv*" -print
/etc/openvpn/update-resolv-conf
find: ‘/run/user/1000/gvfs’: Permission denied
find: ‘/run/user/1000/doc’: Permission denied
this is my ubuntu24. I have a /etc/ dir, a /etc/openvpn/ dir
user@u24:~$ ls /etc/openvpn/
client server update-resolv-conf
Manual Installation:
sudo apt-get install openvpn.sudo openvpn --config /path/to/file.ovpnovpn is a file extention.
Download pia-linux-3.7.2-08420.run and sh pia-linux-3.7.2-08420.run
user@u24:~$ sh pia-linux-3.7.2-08420.run
Verifying archive integrity… 100% MD5 checksums are OK. All good.
Uncompressing Private Internet Access 100%
Installing PIA for x86_64, system is x86_64
[sudo] password for user:
Reading package lists… Done
Building dependency tree… Done
Reading state information… Done
libxkbcommon-x11-0 is already the newest version (1.6.0-1build1).
libxkbcommon-x11-0 set to manually installed.
libnl-3-200 is already the newest version (3.7.0-0.3build1.1).
libnl-3-200 set to manually installed.
libnl-route-3-200 is already the newest version (3.7.0-0.3build1.1).
libnl-route-3-200 set to manually installed.
iptables is already the newest version (1.8.10-3ubuntu2).
iptables set to manually installed.
psmisc is already the newest version (23.7-1build1).
psmisc set to manually installed.
libatomic1 is already the newest version (14.2.0-4ubuntu2~24.04.1).
libatomic1 set to manually installed.
The following additional packages will be installed:
libutempter0
Suggested packages:
xfonts-cyrillic
Recommended packages:
luit | x11-utils
The following NEW packages will be installed:
libutempter0 xterm
0 upgraded, 2 newly installed, 0 to remove and 7 not upgraded.
Need to get 893 kB of archives.
After this operation, 2,556 kB of additional disk space will be used.
Get:1 Index of /ubuntu noble/main amd64 libutempter0 amd64 1.2.1-3build1 [9,606 B]
Get:2 Index of /ubuntu noble/universe amd64 xterm amd64 390-1ubuntu3 [883 kB]
Fetched 893 kB in 1s (717 kB/s)
Selecting previously unselected package libutempter0:amd64.
(Reading database … 197179 files and directories currently installed.)
Preparing to unpack …/libutempter0_1.2.1-3build1_amd64.deb …
Unpacking libutempter0:amd64 (1.2.1-3build1) …
Selecting previously unselected package xterm.
Preparing to unpack …/xterm_390-1ubuntu3_amd64.deb …
Unpacking xterm (390-1ubuntu3) …
Setting up libutempter0:amd64 (1.2.1-3build1) …
Setting up xterm (390-1ubuntu3) …
Processing triggers for hicolor-icon-theme (0.17-2) …
Processing triggers for gnome-menus (3.36.0-1.1ubuntu3) …
Processing triggers for libc-bin (2.39-0ubuntu8.7) …
Processing triggers for man-db (2.12.0-4build2) …
Processing triggers for desktop-file-utils (0.27-2build1) …
Installed packages
Added group piavpn
Added group piahnsd
Copied Private Internet Access files
Allow non-root /opt/piavpn/bin/pia-unbound to bind to privileged ports
Created var folder
Installed icon
Created desktop entry
Set wgpia interface to be unmanaged
Created piavpn service
Created symlink /etc/systemd/system/multi-user.target.wants/piavpn.service → /etc/systemd/system/piavpn.service.
Started piavpn service
user@u24:~$
PIA installs in /opt/piavpn
user@u24:~$ ls /opt/piavpn/
bin etc lib plugins qml share varNot logging out but restarting daemons in user space one by one beginning with vpn client and testing connectivity after each might help finding the one that is breaking your connection.
This may be a stupid question, but how do I determine all running daemons on my system (well, the ones that affect my (inter)net connection)?
systemctl --no-pager --user list-units --type=service --state=running brings up a list of all currently running user daemons. To see not running daemons just drop –state=running from above command.
I guess you have to look up services in this list to find those probably involved in your troubles.
It’s no stupid question. I’m learning much on Ubuntu/Linux myself by trying to help on Ubuntu discourse. And I think my English is slowly improving too.
Thanks for the help. Will do if my i’net connection fails. I’ve learned that one can restart a service/daemon by (example):
systemctl restart piavpn.service