Magento ver. 2.1.7 where I have installed varnish and enabled it from backend after exporting varnish 4 .vcl file. It seems to be working fine and pages which are once loaded do load quickly on the second attempt also shows that under varnish stat in hits and under varnish log.
My question is that once pages are browsed they remain for certain time under varnish cache and then goes away and for any user who is browsing for the very first time it again takes time.
So is there any way through which I can setup kind of cron job or something so my pages are always crawled by Magento 2 varnish so it should always be quicker?
TTFB is always slow but there are sites which do load very quickly always on the first attempt so how they are doing it with varnish?