I am writing a shell script and here is the snippet ..
sudo service httpd restart --- ( 1)
if [ $? -eq 0 ]; then
# Now configure php.ini using sed command
sudo sed -i 's_;date.timezone =_date.timezone = "Asia/Kolkata"_' /etc/php.ini
# Now restart the httpd server again
sudo service httpd restart ---- This statement throws error
When I ran above script then I got error Address already in use: make_sock: could not bind to address at second sudo service httpd restart statement.
I doubt it is because when first time sudo service httpd restart runs , before it finishes completely second 'sudo service httpd restart' runs.
So how can I test surely If first sudo service httpd restart finishes then only rest of the code execute.
I hope I am understandable ..
Thanks
Forget the [ giving:
if sudo service http restart; then
# stuff
if sudo service http restart; then
echo ok
else
# error handling for second service failure
fi
else
# error handling for first failure
fi
Commands are true if their return status is zero, false otherwise. Shell commands also must terminate before the next line is called.
It is possible, in principle, that service does stuff in the background and exits before completion. In practice, it doesn't because that would really screw things up.
Not sure if the command backgrounds. If so, you could check if your command is still to be found in the process list:
// ... your code ...
c=1
while [[ c -gt 0 ]]
do
c=`ps l | grep -c "service httpd restart"`
done
service httpd restart
Related
Is there a parameter I can take from systemctl status ... in order to confirm that a software is running and allow the code to continue? I have the systemctl status command running but with no way to confirm the status. Any help is appreciated.
for example check auditd service using systemctl
sudo systemctl status auditd.service | egrep running; if [ $? -eq 0 ]; then echo "Audit Service is running" else echo "Audit service is not running"; fi
Using single line command you can check service is running or not and can continue with other stuffs.
I am using NodeJs in Raspberrypi on startup (rc.local). i have some issue my ftp client will not able to download data, if the NodeJs run on startup.
but if i run through command line at my own, it will work great and can able to download files through FTP client.
is there any way to see console logs while using nodejs on startup.
My project is already very delayed, please help.
Thanks in advance.
rc.local
`#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.
#sudo neo4j start &
#sudo su pi -c 'sudo neo4j start < /dev/null &'
#sudo su pi -c 'sudo /etc/init.d/mysql start < /dev/null &'
sudo su pi -c 'node /home/pi/Desktop/RaspberyryPiLearning/bin/www <
/home/pi/Desktop/error.log &'
# Print the IP address
_IP=$(hostname -I) || true
if [ "$_IP" ]; then
printf "My IP address is %s\n" "$_IP"
fi
exit 0
You should specify the whole path of node binary file and of your node app, for example : sudo su pi -c '/usr/bin/node /home/pi/node_app/index.js.
You can type which node to get the path of node binary
But, a better option would be to use PM2. It will handle the startup loading of your node apps, handle/display their logs, restart them in case of error. You can monitor them too, stop, restart...
I have a script in cron to check memcached and restart it if it's not working. For some reason it's not functioning.
Script, with permissions:
-rwxr-xr-x 1 root root 151 Aug 28 22:43 check_memcached.sh
Crontab entry:
*/5 * * * * /home/mysite/www/check_memcached.sh 1> /dev/null 2> /dev/null
Script contents:
#!/bin/sh
ps -eaf | grep 11211 | grep memcached
if [ $? -ne 0 ]; then
service memcached restart
else
echo "eq 0 - memcache running - do nothing"
fi
It works fine if I run it from the command line but last night memcached crashed and it was not restarted from cron. I can see cron is running it every 5 minutes.
What am I doing wrong?
Do I need to use the following instead of service memcached restart?
/etc/init.d/memcached restart
I have another script that checks to make sure my lighttpd instance is running and it works fine. It works a little differently to verify it's running but is using the init.d call to restart things.
Edit - Resolution: Using /etc/init.d/memcached restart solved this problem.
What usually causes crontab problems is command paths. In the command line, the paths to commands are already there, but in cron they're often not. If this is your issue, you can solve it by adding the following line into the top of your crontab:
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
This will give cron explicit paths to look through to find the commands your script runs.
Also, your shebang in your script is wrong. It needs to be:
#!/bin/bash
I suspect the problem is with the grep 11211 - it's not clear the meaning of the number, and that grep may not be matching the desired process.
I think you need to log the actions of this script - then you see what's actually happening.
#!/bin/bash
exec >> /tmp/cronjob.log 2>&1
set -xv
cat2 () { tee -a /dev/stderr; }
ps -ef | cat2 | grep 11211 | grep memcached
if [ $? -ne 0 ]; then
service memcached restart
else
echo "eq 0 - memcache running - do nothing"
fi
exit 0
The set -xv output is captured to a log file in /tmp. The cat2 will copy the stdin to the log file, so you can see what grep is acting upon.
Save below code as check_memcached.sh
#!/bin/bash
MEMCACHED_STATUS=`systemctl is-active memcached.service`
if [[ ${MEMCACHED_STATUS} == 'active' ]]; then
echo " Service running.... so exiting "
exit 1
else
service memcached restart
fi
And you can schedule it as cron.
We have a mail server that is dying and in the process of having accounts migrated to a new server before decommissioning. With 800+ email accounts across 25+ domains, it is important for this machine to stay up until migration is finished.
Lately it has started to fill up with error logs, which freeze mysql because of no space, stop mail flow, and generally give me a headache. Until the root problem of the errors can be found and fixed, I have come up with a script to check if Dovecot and Amavis-new are running, and if not restarts them.
After reading:
https://stackoverflow.com/a/7096003/4820993
As well as a few other common examples, I came up with this.
netstat -an|grep -ce ':993.*LISTEN' >/dev/null 2>&1
if [ $? = 0 ]
then
echo 'Dovecot is up';
else
echo 'Dovecot is down, restarting...';
/etc/init.d/dovecot restart
logger -p mail.info dovecot_keepalive: Dovecot is down, restarting...
fi
/etc/init.d/amavis status |grep -ce 'running' >/dev/null 2>&1
if [ $? = 0 ]
then
echo 'AmavisD is up';
else
echo 'AmavisD is down, restarting...';
/etc/init.d/amavis restart
sleep 2
/etc/init.d/amavis status |grep -ce 'running' >/dev/null 2>&1
if [ $? = 1 ]
then
echo 'AmavisD had a problem restarting, trying to fix it now...';
logger -p mail.info amavis_keepalive: AmavisD had a problem restarting...
output=$(ps aux|grep a\[m\]avisd)
set -- $output
pid=$2
kill $pid
rm /var/run/amavis/amavisd.pid
/etc/init.d/amavis start
else
echo 'AmavisD restarted successfully';
logger -p mail.info amavis_keepalive: AmavisD is down, restarting...
fi
fi
Who knows, I'm probably making it harder that it is, and if so PLEASE LET ME KNOW!!!
I checked it against http://www.shellcheck.net and updated/corrected according to it's debug reports. I am piecing this together from examples elsewhere and would love someone to proofread this before I implement it.
The first part checking dovecot is already working just fine as a cronjob every 6 hours (yes the server is that messed up that we need to check it), it's the section about amavis I'm not sure about.
You can use Monit which will monitor your services and restart itself.
Amavisd:
# File: /etc/monit.d/amavisd
# amavis
check process amavisd with pidfile /var/amavis/amavisd.pid
group services
start program = "/etc/init.d/amavisd start"
stop program = "/etc/init.d/amavisd stop"
if failed port 10024 then restart
if 5 restarts within 5 cycles then timeout
Dovecot:
# File: /etc/monit.d/dovecot
check process dovecot with pidfile /var/run/dovecot/master.pid
start program = "/etc/init.d/dovecot start"
stop program = "/etc/init.d/dovecot stop"
group mail
if failed host localhost port 993 type tcpssl sslauto protocol imap then restart
if failed host localhost port 143 protocol imap then restart
if 5 restarts within 5 cycles then timeout
depends dovecot_init
depends dovecot_bin
check file dovecot_init with path /etc/init.d/dovecot
group mail
check file dovecot_bin with path /usr/sbin/dovecot
group mail
What's the difference between:
sudo /etc/init.d/apache2 restart
and
sudo service apache2 restart
I tried the first one, and it didn't apply my changes, while
sudo service apache2 restart
did uptake my changes.
Here is what is actually happening when you run sudo /etc/init.d/apache2 restart:
if ! $APACHE2CTL configtest > /dev/null 2>&1; then
$APACHE2CTL configtest || true
log_end_msg 1
exit 1
fi
if check_htcacheclean ; then
log_daemon_msg "Restarting web server" "htcacheclean"
stop_htcacheclean
log_progress_msg apache2
else
log_daemon_msg "Restarting web server" "apache2"
fi
PID=$(pidof_apache) || true
if ! apache_wait_stop; then
log_end_msg 1 || true
fi
if $APACHE2CTL start; then
if check_htcacheclean ; then
start_htcacheclean || log_end_msg 1
fi
log_end_msg 0
else
log_end_msg 1
fi
As you can see; first a config test is run, if this is successful the server is stopped and then started.
I find it hard to believe that running this command did not apply your changes if they were properly saved and valid. I only use this command and have never had that issue.
/usr/bin/service is described as:
# A convenient wrapper for the /etc/init.d init scripts.
And it does the following:
SERVICEDIR="/etc/init.d"
# Otherwise, use the traditional sysvinit
if [ -x "${SERVICEDIR}/${SERVICE}" ]; then
exec env -i LANG="$LANG" PATH="$PATH" TERM="$TERM" "$SERVICEDIR/$SERVICE" ${ACTION} ${OPTIONS}
else
echo "${SERVICE}: unrecognized service" >&2
exit 1
fi
So the commands are basically identical, sudo service apache2 restart is just a wrapper for sudo /etc/init.d/apache2 restart.
You may also use sudo /etc/init.d/apache2 reload, this reloads the config without restarting the server. This only works if you have changed config, it will not load modules that you have enabled, for that you need to restart Apache.
Edit: This code is from a Debian system.
In general, whether these two commands are identical or not depends on your Linux distribution.
The first one requires the existence of a traditional SysV-style init script. Until a few years ago that was practically the only way to control services and the service script was just a simple wrapper that basically added the init script path.
These days many Linux distributions have switched to alternative service management systems such as upstart or systemd. Therefore, the service wrapper may also make use of these systems, providing a certain degree of compatibility.
Bottom line: depending on the specifics of your Linux distribution, the /etc/init.d/apache2 may not exist at all, it may just use service itself, or it may do nothing at all. My Mageia Linix system, for example, launches Apache using a systemd service file and has no SysV init script at all for it.
You are generally better off just using service <service> <command>....