Translate

Image of Operating System Concepts
Image of Beginning Google Maps API 3
Image of Modern Operating Systems (3rd Edition)
Image of XSLT 2.0 and XPath 2.0 Programmer's Reference (Programmer to Programmer)

Accessing VMware Guest Virtual Serial Port on Linux Host

In this post I show you how to telnet to an emulated serail port of a VMware guest VM running on a Linux host.

Mask V Disable a Systemd Service Unit

In the systemd world, you should be aware of the difference between disabling and masking a service unit. To prevent a service unit that corresponds to a system service from being automatically started at boot time: # systemctl disable name.service When invoked systemd reads the [Install] section of the selected service unit and removes the appropriate symbolic link. In RHEL7, for example, the symbolic link would be to the /usr/lib/systemd/system/name.service file from the /usr/lib/systemd/system/ directory. Every service unit that is known to systemd may be started if it is needed – even if it is disabled. To explicitly tell systemd

The Syslog Protocol

I have used syslog for over 30 years now but other than knowing that it uses UDP and port 514, I have never looked at the underlying protocol in any detail. Syslog is standardized by the IETF in RFC 5424 This document describes the syslog protocol, which is used to convey event notification messages. This protocol utilizes a layered architecture, which allows the use of any number of transport protocols for transmission of syslog messages. It also provides a message format that allows vendor-specific extensions to be provided in a structured way. This RFC does not define any transports. They