Suricata

As you are using systemd to start Suricata, can you tell us what Linux distribution you are using and how you installed Suricata?

You might get some idea of why its failing but running the command manually:

/usr/bin/suricata -c /etc/suricata/suricata.yaml -i wlp2s0 -S /var/lib/suricata/rules/my.rules

Note that I dropped the -D, you'll probably want to do that in your systemd configuration as well, as you usually don't want to daemonize a process when running under systemd.

Yes I use systemd to start suricata. Linux distribution is Ubuntu 20.04 and I installed suricata with Binary packages.
When I run the command manualy, I get this:

suricata@suricata-Latitude-E5540:~$ /usr/bin/suricata c /etc/suricata/suricata.yaml -i wlp2s0 -S /var/lib/suricata/rules/my.rules
8/7/2020 - 17:13:40 - <Error> - [ERRCODE: SC_ERR_CONF_YAML_ERROR(242)] - Failed to parse configuration file at line 1080: found character that cannot start any token

Did you edit the configuration file at all? It looks like there is an error at line 1080 in /etc/suricata/suricata.yaml. The YAML file is sensitive to indentation so that is the first thing to check.

Also, what version of Suricata is this? "suricata -V" should tell you that.

I update the file, and now when I run suricata I got this:
root@suricata-Latitude-E5540:~# suricata c /etc/suricata/suricata.yaml -i wlp2s0
9/7/2020 - 05:28:33 - <Notice> - This is Suricata version 5.0.3 RELEASE running in SYSTEM mode
9/7/2020 -- 05:28:52 - <Warning> - [ERRCODE: SC_ERR_SYSCALL(50)] - Failure when trying to set feature via ioctl for 'wlp2s0': Operation not supported (95)
9/7/2020 -- 05:28:52 - <Notice> - all 4 packet processing threads, 4 management threads initialized, engine started.

1- Can you give me the whole "-c" command line? I use anathor method to do it
2- What I do when I when to stop engine proprely?

Corinne Yakpe wrote in #note-6:

I update the file, and now when I run suricata I got this:
root@suricata-Latitude-E5540:~# suricata c /etc/suricata/suricata.yaml -i wlp2s0
9/7/2020 - 05:28:33 - <Notice> - This is Suricata version 5.0.3 RELEASE running in SYSTEM mode
9/7/2020 -- 05:28:52 - <Warning> - [ERRCODE: SC_ERR_SYSCALL(50)] - Failure when trying to set feature via ioctl for 'wlp2s0': Operation not supported (95)
9/7/2020 -- 05:28:52 - <Notice> - all 4 packet processing threads, 4 management threads initialized, engine started.

1- Can you give me the whole "-c" command line? I use anathor method to do it
2- What I do when I when to stop engine proprely?

That looks OK. At least its up and running. I suspect the error is due to the wireless interface, it might not support all the offloads Suricata is trying to disable for you. You might want to add "-k none" as its likely Suricata may miss some packets due to bad checksums.

There is some documentation on offloads here, but it also comes down to your chipset and other variables. But it looks like you are more or less running. Just might want to add -k none.