Systemd shutdown service problem

nacheitor · 01-10-2019, 12:07 PM

Hi, I have created a file /lib/systemd/system/my-service.service like this:

Code:

[Unit]
Description=My Service
After=network-online.target

[Service]
Type=oneshot
ExecStart=/bin/true
RemainAfterExit=true
ExecStop=ping www.google.com

[Install]
WantedBy=network-online.target

The service start and stops correctly but, I obtain the next output:

Code:

PING www.google.com (172.217.17.4) 56(84) bytes of data.
64 bytes from mad07s09-in-f4.1e100.net (172.217.17.4): icmp_seq=1 ttl=53 time=11                                                                                                             .0 ms
64 bytes from mad07s09-in-f4.1e100.net (172.217.17.4): icmp_seq=2 ttl=53 time=10                                                                                                             .0 ms
64 bytes from mad07s09-in-f4.1e100.net (172.217.17.4): icmp_seq=3 ttl=53 time=69                                                                                                             .9 ms
ping: sendmsg: The network is inaccessible
ping: sendmsg: The network is inaccessible
ping: sendmsg: The network is inaccessible
ping: sendmsg: The network is inaccessible
ping: sendmsg: The network is inaccessible

In the begining of execution of the service the network is up but in the middle of the exetion the networg goes down.

How could I stop the rest of the services until my-service ends?

Thanks in advance.

berndbausch · 01-11-2019, 07:52 AM

my-service will never end. The ping program just goes on until it’s interrupted. You can limit the number of echo packets with the -c (count) option. There are also two timeout options, -w and -W.

nacheitor · 01-11-2019, 12:40 PM

Hi, berndbausch. I know that the ping program just goes on until it’s interrupted. I used the ping program to know if I have Internet access available for the time necessary to update my distribution packages, I used it only for testing purposes. And I have verified that I only receive 3 pings before losing the connection.

Thanks for your help.

berndbausch · 01-11-2019, 06:11 PM

Do I understand you right: You want to perform an action when the system shuts down, but you need internet access to accomplish it?

If so, I have no experience with it, but googling for systemd shutdown sequence yields a few promising results, such as https://superuser.com/questions/1016...016848#1016848.

ondoho · 01-12-2019, 02:44 AM

Quote:

Originally Posted by nacheitor

I have created a file /lib/systemd/system/...

there's your first error there.
you should've created that file in /etc/systemd/system instead.
read the docs.

i also find your service file a little convoluted:

Code:

[Service]
Type=oneshot
ExecStart=/bin/true
RemainAfterExit=true
ExecStop=ping www.google.com

all this to keep the machine online during shutdown?
not sure what would be better, but this doesn't seem the right way.
why not simply create a service that runs upgrades on shutdown, before the network shuts down?
have you tried searching "systemd run updates during shutdown" or some such?

the problem you are seeing is that something else is shutting down important parts of the system/networking while your ping is running. could be DNS, could be sth else.