I know this an old question but I am having a tough time in understanding the linux runlevels w.r.t gracefully stopping and starting a service. For suppose consider myscript service is configured to auto-start after a system shutdown/reboot.
Below is the output of chkconfig command (RHEL 6.5x):
[testfolk#jomohost ~]$ sudo chkconfig --list|grep myscript
myscript 0:off 1:off 2:on 3:on 4:off 5:on 6:off
I understand that myscript service auto-starts on system startup. But what takes care of it's gracefull stop/shutdown task. What if myscript is a delicate service and need to be stopped at any cost before any reboot/shutdown or the application gets corrupted. Is taken care of by default ?
Can I configure it something like below to do a graceful auto stop:
[testfolk#jomohost ~]$ sudo chkconfig --list|grep myscript
myscript 0:on 1:off 2:on 3:on 4:off 5:on 6:on
My assumption of above configuration is the myscript service gets auto stopped on invoking init 6 or init 0. Is this a valid config, I can be completely wrong, please advise. I searched as many articles as possible but all of them were talking about auto-start of a service after a reboot or shutdown but not auto-stop. I am not sure if I am understanding this whole thing correctly, pls help if you have any info!
Thanks in advance for your time!
Related
I need to run some services on boot up which I have successfully accomplished using systemd services. (Lots of answers already available).
Now, one of my service requires access to /dev/video0 while bootup when a certain user is logged in. (I am doing auto login which is working fine).
So how do I check that whether the /dev/video0 is available before starting my systemd service while bootup.
I came across something called udev for doing this, I followed this link
but I am not getting desired output as after editing /lib/udev/rules.d/99-systemd.rules files as mentioned in the link and starting my service manually it's not starting, any help is appreciated.
Finally after struggling for a day I found the answer -
I made a script in /etc/systemd/system which contains
[Unit]
Description='some description of my file write according to you'
[Service]
Type=forking
ExecStart='path to script'
[Install]
WantedBy=multi-user.target
and It executes a script which contains
#!/bin/bash
modprobe uvcvideo
Now after rebooting all the services are running properly
mod probe uvcvideo command check for running video driver and enable it at the time of bootup so that It is available for my systemd process
Thanks
I'm just trying to do a POC test with Telium's HAAst before we offer it to a customer, but I've stalled before I start the haast daemon. Currently I have a single VM with Ubuntu 16.04 LTS with Digium's basic Asterisk 13 installation. I've configured haast.conf, it seems good, but I cannot start haast daemon, it stops after a few seconds. Here is the relevant log output:
General, HAAst version 2.3.2.1 starting as daemon under process ID 2409
Controller, Local peer HAAst state changing to service start
License, License file not found. Switching to Free Edition
General, Settings contained 0 information; 0 warning; and 0 error messages.
Asterisk Controller, Unable to located executable to control Asterisk
Controller, Local peer HAAst state changing to service stop
Controller, Stopped
General, HAAst terminating with exit code 158 (failure to find asterisk control files) after running for 2 seconds
It seems, haast misses the event controller to start Asterisk daemon, unfortunately it didn't contain the installation package. I've tried to make these files (asterisk.start & asterisk.stop) based on the other sample event files, I've set the executable bit, I've wrote the shebang to the first line based on the installation guide, but nothing helped.
Is somebody experienced about this case?
Thanks, Zsolt
This error means that High Availability for Asterisk (HAAst) is unable to find the service/executable file needed to control Asterisk. Since the 'distribution' setting in the [asterisk] stanza of the haast.conf file is it to 2 (Digium Asterisk), it means there's a problem with the Asterisk service file.
Ubuntu 16 uses systemd so have you installed Digium's asterisk.service (systemd) file? If you chose to install an initd service file for Asterisk instead then you may have to explicitly tell HAAst which to look for. If you installed neither then that's your problem. The maker of HAAst (Telium) has a support forum where this topic is addressed (click here).
The pre and post Asterisk event handlers are available in the commercial versions of HAAst only - so that won't help (but it's also the wrong way to solve the problem). There are also a few Ubuntu specific topics on the support forum https://www.telium.io/haast in case that helps.
If you can't find an Asterisk systemd service file here's a sample:
[Unit]
Description=Asterisk PBX and telephony daemon
Documentation=man:asterisk(8)
Wants=network.target
After=network.target
[Service]
Type=simple
User=asterisk
Group=asterisk
ExecStart=/usr/bin/asterisk -f -C /etc/asterisk/asterisk.conf
ExecStop=/usr/bin/asterisk -rx 'core stop now'
ExecReload=/usr/bin/asterisk -rx 'core reload'
[Install]
WantedBy=multi-user.target
Just save that file as 'asterisk.service' and place in /etc/systemd/system/ and ensure permissions match other service/unit files.
Haast configuration is missing or not correct:
Unable to located executable to control Asterisk
I was in riak-shell when ssh lost its connection to the server. After reconnecting, I do the following:
sudo riak-shell
and get:
An instance of riak-shell is already running
So, I restarted the riak node in question. This did not seem to solve the problem. I do not see anything using ps -aux to kill. According to the docs, only one instance can run at a time. That makes sense, but when I run riak-shell from another node and try to connect to any node, I now get the following:
Error: invalid function call : connection_EXT:connect ["riak#<<<ip_address_elided>>>"]
You can connect to a specific node (whether in your riak_shell.config
or not) by typing 'connect "dev1#127.0.0.1";' substituting your
node name for dev1.
You may need to change the Erlang cookie to do this.
See also the 'reconnect' command.
Unhandled message received is {#Ref<0.0.0.135>,disconnected}
riak-shell(3)>
I have not changed the cookies during this process, and the cookie appears to be the same (at least in /etc/riak/riak_shell.config). (I am running the Riak TS AMI on AWS.)
riak-shell runs in its own Erlang VM - entirely separate from the riak node
(You don't need to run riak-shell from the machine your node is on - it uses the normal riak-erlang-client to talk to riak)
If you you are on a Linux do ps aux | grep riak_shell_app it will give you the process number you need to kill that instance:
08:30:45:~ $ ps aux | grep riak_shell_app
vagrant 4671 0.0 0.3 493260 34884 pts/4 Sl+ Aug17 0:03 /home/vagrant/riak_ee/dev/dev1/erts-5.10.3/bin/beam.smp -- -root /home/vagrant/riak_ee/dev/dev1 -progname erl -- -home /home/vagrant -- -boot /home/vagrant/riak_ee/dev/dev1/releases/2.1.1/start_clean -run riak_shell_app boot debug_off /home/vagrant/riak_ee/dev/dev1/bin/../log/riak_shell/riak_shell -noshell -config /home/vagrant/riak_ee/dev/dev1/bin/../etc/riak
I wrote a good chunk of it so let me know how you got on:
https://github.com/basho/riak_shell/graphs/contributors
What is the proper way to run Kibana 4.5 as service on CentOS 7?
When I run it as ./kibana, I can conenct to it form another machine without any problem. When I run it with systemctl start kibana and check with ps -ef | grep '.*node/bin/node.*src/cli'it looks like running but refuses to connect. And goes down. What can be the problem? Thanks in advance.
Here is content of kibana.service file
[Unit]
Description=no description given
[Service]
Type=simple
User=kibana
Group=root
Environment=CONFIG_PATH=/opt/kibana/config/kibana.yml
ExecStart=/opt/kibana/bin/kibana
Restart=always
[Install]
WantedBy=multi-user.target
I am not that much of a linux expert but i recently installed kibana using yum (https://www.elastic.co/guide/en/kibana/4.5/setup.html#kibana-yum) on a minimal installation of CentOS 7 and did not face any issues whatsoever.
In order to have some debug logs and find out what is wrong in your case, edit the kibana configurations file
/opt/kibana/config/kibana.yml
and set a filename for the logging.dest property.
logging.dest: /var/log/kibana.log
Good luck
Igor,
I noticed a few questions you posted on Kafka so sounds like you need to set up a cluster that can ingest data and pass to Elastic. Kibana would be just user interface.
In my experience, components like ELK, Kafka, Zookeeper, etc should be managed by a watchdog process. I highly recommend looking at something like supervisord. http://supervisord.org/
You should run it as a service and the rest managed by the supervisor. It will guarantee starting components at boot but whats more important restart in case of failure and collecting logs. In case of Kibana, it is a NodeJS app that writes to stdout/stderr so to know what fails, you need to collect them.
I've set up a Flask application to run on a tornado server backed by nginx. I've written a couple of bash scripts to reload server configuration when a new version is deployed, but I am unhappy with them. Basically what I have is:
to start the server (assuming in project root)
# this starts the tornado-flask wrapper
python myapp.py --port=8000 # .. some more misc settings
# this starts nginx
nginx
to stop it
pkill -f 'myapp.py'
nginx -s stop
to restart
cd $APP_ROOT
./script/stop && ./script/start
Many times these don't work smoothly and I need to manually run the commands. Also, I'm looking for a way to verify the service is alive, and start it up if it's down. Thoughts? Thanks.
Supervisor is what you are looking for.
It's what I use to manage my Tornado apps along with some other processing daemons.
It will daemonize, handle logging, pid files... Pretty much everything you need.