Installing the Varnish software is beyond the scope of this guide. For more information about installing Varnish, see:
This topic is written for Varnish on CentOS and Apache 2.4. If you are setting up Varnish in a different environment, some commands are likely different. Consult the preceding documentation for more information.
If you intend to install Varnish modules (vmods), such as saint mode, you should install Varnish by compiling the code, rather than installing from a package. See Saint mode for more details.
Open a terminal and enter the following command to display the version of Varnish:
varnishd -V
A sample follows:
varnishd (varnish-6.3.2 revision 199de9b)
Copyright (c) 2006 Verdens Gang AS
Copyright (c) 2006-2019 Varnish Software AS
Make sure that the version is 6.x before continuing. If you are running version lower than 6.x, you must upgrade to a supported version. Consult the Varnish installation documentation for more information.