Posts Categorized: linux

Manic Miner on Linux

I was reminded about how much time I had spent as a kid playing Manic Miner on an Amstrad 464 and decided to give it a try on my current desktop (Linux Mint) so for future reference… I grabbed the code created by here:

Installed a few dependencies:

Run the make file:

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rpcbind.socket failed to listen on sockets: Address family not supported by protocol

Using CentOS 7 this problem arose after a reboot and NFS shares would not mount. Trying to start the rpcbind service:

gave the following error message via jounralctl -xe :

So it looks like

was set in /etc/sysctl.conf But this wasn’t yet incorporated into the initramfs. Solution Rebuild the initramfs with:

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Mount Files Virtually via Dell iDRAC

Use fallocate to create a new 300 MB file :

Create an ext4 file system within the image file:

Create a mount point:

mount it:

Then on the Dell iDRAC use the ‘Virtual Media’ menu to ‘Map Removable Disk…’  : Then on the host operating system the device can be mounted… Read more »

Determine Dell Hard Disk Location from Linux

On a Dell server I needed to determine the physical hard drive location for a faulty disk. Within the operating system the disk was mounted as /dev/sdk so I ran:

And from the output I could correlate this with the information in the iDRAC: So in this example disk 10 on the backplane.  

Dell racadm on Linux

I’m currently using Linux Mint and wanted to communicate with the iDRAC interfaces on Dell servers. Install racadm:

Test with:

or if you want to be prompted for login credentials use:

Example racadm commands Dump lots of info:

Get the status of the PERC/Raid battery:

Set… Read more »

Command Line Optimise JPEG image

This command significantly improved file size on disk although the quality value can be increased to adjust the image quality versus file size:

 

Apache: unable to open logs

In the annals of “Everyday is a learning day”. I have an Apache server hosting student websites, and the number of websites grew to over 700 within a day and Apache was complaining with error:

It took a little while to narrow down the problem as I assumed there was a path that did… Read more »

Locating Excessive Inode Usage

The command to list the directories using the most inodes is:

However, I first needed to narrow down the directory under root that might be causing the problem:

showed that the root directory (/) was the problem. But I did not need to scan all directories as some had terabytes of files so:… Read more »

Configure Java Security Settings on Linux

I received the following error message when trying to run a Java JNLP file: Application Blocked by Security Settings Your security settings have blocked a self-signed application from running Assuming I trust the program I found I could get it to run by amending the Java Security Policy: Amending the Java Security Policy The first… Read more »

Intel Xeon Phi Co-Processor Setup

centos logo

Introduction Just adding my notes here in case it helps anyone else who finds themselves in a similar situation to me.I have two machines each with an Intel Xeon Phi Co-Processor board. This (in my basic view of the world) is like an extra machine inside the host machine but contains 240 processors clocking in… Read more »