Verify the status of a running process
To address the issue of the code always returning ‘OK’ due to grep finding itself in the process list, consider using a different approach. One possible solution involves searching for the exact process instead of just the word ‘file’. This way, you can determine if the file exists or not without displaying unnecessary information.
Check if process is running
My goal is to determine if check if a process is currently operational. To achieve this, I require a response of ‘OK’ if it is operational and ‘Not OK’ if it is not. I am restricted to using ‘ps’ exclusively, without any additional arguments such as ps -ef. The code I am currently using is:
if ps | grep file; then echo 'OK'; else echo 'NO'; fi The issue with this approach is that it does not perform a precise process search and consistently displays ‘OK’. I am not interested in viewing all the details; my only concern is to determine the presence or absence of the file.
The reason why your code consistently returns ‘OK’ is because grep is able to locate itself in the process list due to the presence of the word ‘file’ in ‘grep file’. To resolve this issue, consider using `grep -e [f]ile’ (-e for regular expression) to prevent self-referencing.
Save grep for genuine issues.
Eliminates the need for utilizing grep thereby preventing the issue.
When I know the pid I prefer:
[ -d /proc/ ] && echo OK || echo NO Ssh — Check if remote process is running (linux), else echo «Process is not running.» fi However, I’d like to modify this to check if the process is running on another machine, without ssh’ing directly, since this breaks me out of the current script if I’m running it in a loop. In essence, I’d like to do this: ssh otherMachine ps cax | grep my_script.sh > /dev/null if [ $? -eq 0 ] then echo
How to find what processes were running at a time in the past?
Earlier today, I was tasked with investigating a high CPU usage alert. To carry out the investigation, I utilized sar -p and was able to detect the occurrence of high CPU usage during that specific time period.
I utilized the code ps -eo pcpu,pid,user,args | sort -r -k1 | less to display the top 10 processes consuming the most memory presently.
As a Java developer and not a Linux expert, I’m unsure how to determine the processes that caused the bottleneck at specific time in the morning.
There are several options:
- One way to consistently record necessary information is by utilizing a script that writes data to a logfile at regular intervals. To achieve this, you may consider utilizing cron to write the output of various commands, such as ps, into a logfile every x minutes.
- Using a specialized program is more efficient than manually handling log file retention. atop is a reliable tool for this task.
Atop can be accessed through the EPEL repository for CentOS/RHEL/Fedora, and it is also available in the default repositories for Debian/Ubuntu.
Atop can function like a typical real-time top tool, but with minor variations in its operation (refer to the manpage for key commands).
The intriguing aspect is that upon installation, a daemon will commence recording data in the /var/log/atop directory, which can be accessed and examined using atop.
atop -r /var/log/atop/atop_20160128 Once you gain entry, you will be able to utilize all of the superior features such as sorting, examining memory, CPU and IO usage, and more. Additionally, you have the capability to advance 10 minutes into the future using ‘t’ or backtrack 10 minutes with ‘T’. Alternatively, you can move to a particular time by using ‘b’.
Explore the atop manual page and find numerous how-to guides on Google.
Although there could be alternative methods, atop is a simple and user-friendly option that serves as a helpful starting point prior to implementing more customized configurations.
How to check if process is running in linux, From inside a program, this is a common way to check that a process of known pid is still existing and running (or waiting). You could use the pidof command to find the processes running some executable, e.g. pidof zsh to find all the zsh processes. You could also use killall -s 0 zsh
Best practice to check if a process is running on Linux?
As a beginner in Linux, I utilized the script provided by chef.io to install the chef server successfully. However, I am unsure about the process running status of check if the process. Can you suggest some best practices to determine if a process is running on Linux? Additionally, what steps should I take to gather the necessary information?
#!/bin/bash \ echo "Do your provisioning here" \ sudo wget https://packages.chef.io/files/stable/chef-server/12.14.0/el/7/chef-server-core-12.14.0-1.el7.x86_64.rpm \ sudo chmod a+x chef-server-core-12.14.0-1.el7.x86_64.rpm sudo rpm -Uvh ./chef-server-core-12.14.0-1.el7.x86_64.rpm sudo chef-server-ctl reconfigure \ sudo openssl rsa -in private.pem -outform PEM -pubout -out ~/.ssh/chef-server.pem \ sudo chef-server-ctl user-create admin 'admin' 'email' 'password' --filename ~/.ssh/chef-server.pem \ sudo openssl rsa -in private.pem -outform PEM -pubout -out ~/.ssh/chef-server-validator.pem \ sudo chef-server-ctl org-create short_name 'idevops' --association_user admin --filename ~/.ssh/chef-server-validator.pem \ sudo openssl rsa -in private.pem -outform PEM -pubout -out ~/.ssh/chef-coffee-server-validator.pem \ sudo chef-server-ctl org-create 4thcoffee 'iDevops 4th Coffee' --association_user admin --filename ~/.ssh/chef-coffee-server-validator.pem \ sudo chef-server-ctl install chef-manage \ sudo chef-server-ctl reconfigure \ sudo chef-manage-ctl reconfigure \ sudo chef-server-ctl install opscode-push-jobs-server \ sudo chef-server-ctl reconfigure \ sudo opscode-push-jobs-server-ctl reconfigure \ sudo chef-server-ctl install opscode-reporting \ sudo chef-server-ctl reconfigure \ sudo opscode-reporting-ctl reconfigure \ sudo chef-server-ctl install PACKAGE_NAME --path /path/to/package/directory \ sudo chef-server-ctl install chef-manage --path /root/packages \ sudo mkdir /etc/opscode && sudo touch /etc/opscode/chef-server.rb \ sudo echo "license['nodes'] = 0" >> /etc/opscode/chef-server.rb \ sudo chef-server-ctl reconfigure To locate them on the internet, begin by verifying whether the process is active.
ps aux | grep process_name
In case the server is active but inaccessible, utilize the netstat command and search for the port using grep.
net stat -anp | grep portnumber To check if the service is running on the correct port, verify if it’s listening. When it’s listening, it indicates that the port is actively seeking communication. This suggests that the application is operational and actively seeking communication on the port. However, if the port is already in use by another application, it won’t start.
To view the last 100 lines of a log file, one can use the command «tail -f -n 100 /path/to/log/file». The option «-n» specifies the number of lines to display, while «-f» enables continuous following of the file. Without «-f», only the first 100 lines will be displayed on the screen.
To perform a manual check, access the server and execute the following command.
ps auxw | grep YOUR_PROCESS_NAME Initially, I refrain from executing commands from a script without verifying their proper functioning. There is a possibility that the service is not being run by you.
sudo service chef-server status #would be a good place to start If you’re planning to use Check if a process is running on a Linux system, my suggestion would be to begin with the following steps.
ps aux | grep ps aux | grep chef In case you’re dissatisfied with the results produced by ‘aux’, you can opt to use ‘-ef’ instead.
ps -ef | grep ps -ef | grep chef In case you are aware of the specific port that needs to be open for the process, you can utilize netstat.
In search of a running server, specifically either nginx or apache.
My preferred way of monitoring logs is by utilizing the tail command.
Example: watching nginx logs:
tail -f /var/log/nginx/nginx.log At times, it can be beneficial to also monitor the syslog.
tail -f -n 100 /var/log/syslog If searching for external connections from other devices.
sudo tcpdump -vvv -i any port The output you posted contains a significant clue, such as the code labeled as chef-server-ctl status .
The status subcommand is used to show the status of all services available to the Chef server. The results will vary based on the configuration of a given server. or, chef-server-ctl status SERVICE_NAME
where SERVICE_NAME represents the name of any service that is listed after running the service-list subcommand. Additionally, towards the end of the page, you can find the start subcommand under the chef-server-ctl (executable) section.
Linux Script to check if process is running and act on the, I have a process that fails regularly & sometimes starts duplicate instances.. When I run: ps x |grep -v grep |grep -c «processname» I will get: 2 This is normal as the process runs with a recovery process.. If I get 0 I will want to start the process if I get: 4 I will want to stop & restart the process What I need is a way of …
Check if remote process is running (linux)
Here’s the code I’ve written to verify if the script with the name my_script.sh is currently executing:
ps cax | grep my_script.sh > /dev/null if [ $? -eq 0 ] then echo "Process is running." else echo "Process is not running." fi I want to make a change to verify if the procedure is executing on a different device, without directly using ssh. This is necessary to prevent interruption of the current script in case of a loop.
In essence, I’d like to do this:
ssh otherMachine ps cax | grep my_script.sh > /dev/null if [ $? -eq 0 ] then echo "Process is running." else echo "Process is not running." fi ssh originalMachine Assistance of any sort would be welcomed. Many thanks!
It is uncertain if this is what you seek, however, you can perform the check command within an SSH call directly on the remote machine. The output of the invoked command on the remote machine should match the return value.
Naturally, the usage of passwordless authentication method requires enabling, such as through the implementation of ssh keys.
ssh otherMachine "ps cax | grep my_script.sh > /dev/null" if [ $? -eq 0 ] then echo "Process is running." else echo "Process is not running." fi Here’s an uncomplicated method to verify if the program is operational on a remote site.
ssh root@192.168.22.12 -p 22 -t «pgrep -fl while.sh»
if [ $? -eq 0 ]; then echo "Process is running."; else echo "Process is not running."; fi Best practice to check if a process is running on Linux?, First, I do not run commands from a script until I know they work. You may not be running the service: sudo service chef-server status #would be a good place to start To check if a process is running on linux I would recommend starting with the following: ps aux | grep