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JanErik

Member

Registered: 2018-01-08

Posts: 36

Default route lost after suspend

After updating last sunday, it seems my default route is lost after I suspend.
Works normally after I add it with "route add default gw".
I am using systemd.networkd and static IP settings.

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 20,334

Re: Default route lost after suspend

If only we knew whether this was wired or wireless, or what you are using to control your network interface (systemd-network, netctl, NetworkManager), and what desktop environment you might be using (KDE, i3, sway, Gnome)

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JanErik

Member

Registered: 2018-01-08

Posts: 36

Re: Default route lost after suspend

It is wired ethernet and I am using systemd-networkd. Running Plasma.

bschwehn

Member

Registered: 2020-08-21

Posts: 3

Re: Default route lost after suspend

tl/dr: adding IgnoreCarrierLoss=true to the network config seems to be a working workaround for me

I have the same issue since one or two weeks. A third person reports this issue at https://bbs.archlinux.de/viewtopic.php?id=33484 (german).
The common denominator between the three of us seems to be using a static ip address and systemd-networkd.

I don't recall having done any relevant setup changes (other than pacman update) when it started happening.

Usually (90% of the time), the default gateway is gone after waking from suspend. Rarely (10%) of the time, both the static Ip and gateway are gone. Adding the default gateway (and IP, if also missing)  back fixes it until the next suspend, but restarting systemd-networkd also works.

Output after suspend, when the gateway only is gone:

 # networkctl
IDX LINK   TYPE     OPERATIONAL SETUP
  1 lo     loopback carrier     unmanaged
  2 enp4s0 ether    routable    failed

# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.188.0   0.0.0.0         255.255.255.0   U     0      0        0 enp4s0

# journalctl -xeu systemd-networkd
Aug 21 20:33:46 taube systemd-networkd[6280]: enp4s0: DHCPv6 lease lost
Aug 21 20:33:46 taube systemd-networkd[6280]: enp4s0: Reset carrier
Aug 21 20:33:46 taube systemd-networkd[6280]: lo: Reset carrier
Aug 21 20:33:46 taube systemd-networkd[6280]: enp4s0: No static address is stored.
Aug 21 20:33:46 taube systemd-networkd[6280]: enp4s0: Failed

I wonder where the "DHCPv6 least lost" is coming from. I thought setting DHCP to no would disable DHCP for both ipv6 and ipv4.

My network config in /etc/systemd/system/network is:

[Match]
Name=enp4s0

[Network]
Address=192.168.188.180/24
Gateway=192.168.188.1
DNS=192.168.188.210
DHCP=no

Adding IgnoreCarrierLoss=true to the [Network] section makes this issue go away (so far). Not sure if this is the best option however.

Edit: This recent bug report may be relevant: https://github.com/systemd/systemd/issues/16768. I tried adding MTUBytes as the workaround as mentioned in that bug report, but this made no difference for me. I still hope that this systemd fix will fix this issue here also, let's see.
Edit2: Actually, looking at the code fix for the systemd bug makes me doubt that it will fix this issue also.

Last edited by bschwehn (2020-08-21 19:26:07)

goeb

Member

Registered: 2015-06-03

Posts: 11

Re: Default route lost after suspend

tl/dr: adding IgnoreCarrierLoss=true to the network config seems to be a working workaround for me

I have the same issue since one or two weeks. A third person reports this issue at https://bbs.archlinux.de/viewtopic.php?id=33484 (german).
The common denominator between the three of us seems to be using a static ip address and systemd-networkd.

Thanks. I'm having the same issue since systemd 246. Basically the same setup, static IP with systemd-networkd, although I'm running with two bridge interfaces (both are affected).

Usually (90% of the time), the default gateway is gone after waking from suspend. Rarely (10%) of the time, both the static Ip and gateway are gone. Adding the default gateway (and IP, if also missing)  back fixes it until the next suspend, but restarting systemd-networkd also works.

Same here. I thought it was fixed with the systemd 246.2 update, cause everything worked fine once after that. But then it happened again.

Edit: This recent bug report may be relevant: https://github.com/systemd/systemd/issues/16768.

I've seen that bug report, and it was closed before 246.2 hit the repos, so I thought it had been fixed, but I was wrong. I've added the IgnoreCarrierLoss option now, I'll report back tomorrow whether it's working.

bschwehn

Member

Registered: 2020-08-21

Posts: 3

Re: Default route lost after suspend

Same here. I thought it was fixed with the systemd 246.2 update, cause everything worked fine once after that. But then it happened again.

I updated to 246.2 earlier today and 246.2-2 just now, but didn't see any difference.

I believe it is fixed with https://github.com/systemd/systemd/pull/16697 which is backported 246 stable. So I think this fix will come to arch soon

Last edited by bschwehn (2020-08-21 23:19:19)

goeb

Member

Registered: 2015-06-03

Posts: 11

Re: Default route lost after suspend

Great. Until then the IgnoreCarrierLoss=true setting does seem to work.

Jurassic

Member

Registered: 2006-10-31

Posts: 54

Re: Default route lost after suspend

Worked for me to solve the network resume from suspend issue.

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