Category Archives: How To - Page 9

How To Provide NFS Shares For Group Collaboration

How To Provide NFS Network Shares For Group Collaboration and Sharing

Previously we have covered how to provide NFS shares to specific clients, here we are going to expand upon this and cover how an NFS share can be shared with members in a group for collaboration purposes.

This will be done primarily with the use of set group ID (Set GID), as using this results in all files and directories created within the group share being automatically set with the same group owner as the share itself.

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How To Free /boot Disk Space In Linux

Free boot space

By default the size of a /boot partition in Linux is not that big, 512mb or so is quite a typical default. This space is used to store different versions of the Linux kernel that you have concurrently installed at the same time.

If this space fills up you may not be able to perform a kernel upgrade in future so it is important to not let it fill and free up space in /boot.

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How To Configure Network Teaming In Linux

Configure Network Teaming

In Linux it is possible to aggregate multiple network links together into a single logical link which can either increase network throughput or redundancy. For example we can assign an IP address to a group of two network interfaces to double our throughput, or reserve one interface for backup purposes so if the first one fails we can fail over.

Here we’re going to cover how to create and configure a network team with two different network interfaces.

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How To Set GNOME Display Manager Banner Message

GDM Banner

Here we cover how to add a banner message in the GNOME Display Manager (GDM), this message will display in the graphical user interface (GUI) prior to a user logging in.

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How To View BitLocker Disk Status

Bitlocker status

BitLocker is Microsoft’s solution to providing full disk encryption. While setting up BitLocker and encrypting your disk you probably want to check and view the progress and see the current status, as it can take quite a long time depending on the size and speed of your disk.

Here we cover how to view the current BitLocker status in both the graphical user interface, and with PowerShell.

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Configure Squid Proxy To Forward To A Parent Proxy

Here we’re going to take a look at configuring two Squid proxy servers to forward requests from an internal network with no connectivity to the Internet out to a DMZ network and then onto the Internet if required.

The configuration will allow us to select which domains should or should not be forwarded on to the next proxy server, allowing requests that are destined for domains within the internal network to not be forwarded to the next Squid proxy, while other requests to the DMZ network or the Internet will be forwarded to the next proxy.

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How To Disable USB Storage Devices In Linux

How To Disable USB Storage In Linux

By default when you plug in an external USB storage device into a computer running Linux it will automatically mount, allowing the user to access the contents.

This behaviour can be less than ideal from a security perspective, as it can allow an attacker to copy confidential files, or allow a user to run a malicious script stored on the USB device for example.

With some simple configuration changes we can disable USB storage in Linux for unprivileged users.

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How To Defragment An XFS File System

How To Defragment An XFS File System

The XFS file system generally does a pretty good job at keeping itself clean and tidy, however it can still get fragmented over time. Here we’re going to show you how to check the level of fragmentation in place on your XFS file system and how you can defragment it if required, further increasing disk performance.

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How To Search All Files By Date Recursively In Linux

Search Files By Date Recursively In Linux

Have you ever wanted to view a list of all files or subdirectories within a directory in Linux and order them by when they were last changed or modified? Then you have come to the right place! Here we are going to provide and explain some useful commands that when piped together will give us this result, allowing us to recursively list files and directories by date.

This is one of my favourite commands to use when trying to build a timeline of events, for instance if a server or website has been compromised and you want to see when files have been modified with malicious content. By seeing other files that were modified around the same time you can get a better idea of what took place and when, allowing you to correlate these events with your logs.

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How To Synchronize Time in Linux with NTP Peers

Time

There are many different services such as Kerberos that depend on the time of a Linux system being accurate in order to function correctly. It is therefore important to ensure that system time is synchronized with an external source so that it can be kept accurately up to date, this is done with the network time protocol (NTP).

Here we are going to cover how to configure chronyd or ntpd in Linux to connect to an NTP server and keep time in sync. Read more »