Categories
SysOps

How to wipe partition-table signatures with one exception

Today I will extend the how to fix device excluded by a filter blog post to include information on how to wipe filesystem or partition-table signatures except for LVM2 members, which is a great idea for automation.

Categories
SysOps

How to display kernel slab cache information

You can directly inspect kernel slab allocator statistics (/proc/slabinfo file) for detailed information on buffer, inode, dentry, or other caches in the Linux kernel, though slabtop utility will sort and pretty-print information in real-time.

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SysOps

How to disable Network Manager connectivity checks

Four different ways to disable Network Manager connectivity checks.

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SysOps

How to get package URL on CentOS

Sometimes I need to get the package URL on CentOS to store it using Nexus Repository Manager. At first glance, it is not very obvious how to display package URLs, but the actual process is very simple.

Categories
SysOps

How to use Nginx reverse proxy to limit external calls inside web-browser

Use Nginx reverse proxy to add Content-Security-Policy header and disable phoning home or external analytics inside web-browser.

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SysOps

How to dry-run CentOS upgrade process

Use tsflags plugin to test upgrade process before executing it.

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SysOps

How to extend RandR valid modes for an output

Using passive adapters to connect DisplayPort output to HDMI or DVI input is problematic with wide-screen monitors as these adapters supports a maximum resolution of 1920×1200 at 60Hz. This issue can be alleviated by adding a specific mode to the set of valid output modes.

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SysOps

How to write an operating system to microSD card using graphical user interface

Write an operating system to microSD card using Raspberry Pi Imaging Utility.

Categories
SysOps

How to deal with overlapping LVM names

Today, I will connect the secondary encrypted hard disk from the previous Ubuntu installation to copy personal data, so there will be a problem with overlapping LVM names.

Categories
SysOps

How to suppress SSH banner

Suppress SSH banner when executing ad-hoc commands.