Common Linux Commands

tcpdump

Use the following command to capture a packet trace on dsTest's Control Interface if you need to capture RESTful API transactions (use Packet Capture to capture test traffic and ensure that all packets are captured). You must be logged in as root, or operating with root privileges.

          ~> tcpdump -i <interface> -s0 -w <some-file>

free

Use the following command to check the amount of free memory available on your server.

~> free -m -t

shutdown

If the Linux server needs to be shut down, we recommend using the following procedure (requires root privileges). You can use dsTest's wall command to broadcast a message to all connected clients if needed.

          ~> shutdown -h now

ps -ef | grep dsTest

Use the following command to determine whether dsTest is running:

~> ps -ef | grep dsTest

root     14523     1  1 Nov27 ?        00:38:24 /usr/local/devsol/bin/dsTest -B -l6 -L6

devsol   15709 15681  0 14:52 pts/1    00:00:00 grep dsTest

~>

The output of this command shows that dsTest is in fact running.

tar

To compress a set of files, such as for submission to Developing Solutions Support, use the tar command:

          ~> tar -czvf <filename>.tgz <file1.ext> <file2.ext> .... <filen.ext>

NTP

Floating licenses are time-sensitive and dsTest requires that the date and time on the server platform be properly configured. A "License failed to parse" error is generated when dsTest is started without a valid license or when there is a conflict between the license and the configured date and time on the server. We recommend synchronizing the server date and time with an NTP server.

For Ubuntu systems,the choice for fast and accurate time synchronization is chrony. Use the following general instructions for enabling NTP on your dsTest  platform (requires root privileges):

 

Install chrony on the desired server:

~> apt -y install chrony

Start the chrony service:

~> systemctl start chrony

Enable the chrony service:

~> systemctl enable chrony

To verify that chrony is successfully installed and to see the number of servers and peers that are connected, utilize the following commands:

~> systemctl status chrony

~> chronyc activity

~> chronyc sources -v

~> chronyc sourcestats -v

~> chronyc tracking

 

For RHEL systems, use the following general instructions for enabling NTP on your dsTest platform (requires root privileges):

Install chrony on the desired server:

~> apt -y install chronyd

Start the chrony service:

~> systemctl start chronyd

Enable the chrony service:

~> systemctl enable chronyd

To verify that chrony is successfully installed and to see the number of servers and peers that are connected, utilize the following commands:

~> systemctl status chronyd

~> chronyc activity

~> chronyc sources -v

~> chronyc sourcestats -v

~> chronyc tracking