Dec 9, 2012

connect to jboss on a Fedora Linux System from external network

This week I had the problem, that from an external WebSphere portal server, I wanted to connect to a manually started jboss on port 8080.

After some time I recognized, that Fedora 17 has a firewall, which prevented
the connection.

How to enable such a port?

There is a command line system-config-firewall:

This GUI allows to add new ports and apply the changes to the system.

hibernate/suspend with Fedora Linux 17 on a FUJITSU SIEMENS CELSIUS H270/Z118M4A

How to suspend the Fujitsu H270 notebook?

  • I have to disable the external monitor with the nvidia settings ( the free driver doesn't support the external monitor). 
  • I have to disable the network configuration with the network manager
  • I have to release the laptop from the docking station

After this I can suspend the laptop and it is possible to wake up outside the office.

But this weekend I had another problem again. The battery had not that much
power to keep the system in suspend mode available.

After rebooting, I found an option in systemctl - command.

sudo systemctl hibernate

This puts the system to the disk. After poweron, it seems as if a reboot occures,
but the stored system is reloaded and fast available.
And this will not drain the battery.

Dec 5, 2012

How to find a process binding a port on linux - lsof doesn't show the port

Today I had the problem, that a running java process was binding a port and
a new installed process tried to start and bind the same port.

How to find out which process is binding that port?

On Solaris/OpenIndiana/Illumos there is no easy way with onboard tools.

The data is hidden in the proc filesystem. For this area I have since a longer
time the script pcp which is doing the parsing in the proc filesystem to search
for the process.

On Linux, I know from former times, that lsof is doing the job.

The simple form here is lsof -i :<port number>, but I didn't get an output?

The problem was, that the process is running with root privileges and I issued
the command as my normal user.

After starting the command with sudo as root, I got the process.