varnish

Reload your vcl in Varnish without restart

Using varnishadm you can reload your vcl after editing it, without restarting varnish.
That means your cache is intact:

# varnishadm
varnish> vcl.load default /usr/local/varnish/etc/varnish/default.vcl
200
VCL compiled.
varnish> vcl.use default
200

varnish>

What I found really practical was that this way I also could detect and fix errors in my vcl config, without varnish going down.

varnish> vcl.load default /usr/local/varnish/etc/varnish/default.vcl
106        
Message from VCC-compiler:
Expected ')' got '{'
(program line 73), at
('input' Line 105 Pos 51)
        if ( !( req.url ~  "(login_form|manage)") {
--------------------------------------------------#

Running VCC-compiler failed, exit 1
VCL compilation failed