said by Aj137:@hellfire
DSR500n has been config in round robin mode with two ISP. previously i had edited the host file to block Facebook but now after putting the DSR500n it was blocked by using web filter method from past few days its not been blocked AS the Facebook HAS HTTPS in its address i goggled abt that its says u cant block HTTPS sites as its a secure already
So NEED MORE INFO ON THIS
It is not unusual at all for most router based url site blocking to not work with https traffic. The https traffic is encrypted, and the url filtering is not able to see the unencrypted url. I have also seen router based url blocking get defeated when a site had both IPv4 and IPv6 IP addresses, because the router's url blocking only worked for IPv4.
Also, using pseudo DNS "blocking" with a hosts file is often not very effective because the hosts file would have to be constantly updated with every hostname that the site(s) you want to block might decide to use. The only way to do DNS based "blocking" is to setup a DNS server that takes over as the definitive nameserver for every domain you want to block, and setting up your router's security so that every PC will be forced to use only that DNS server for DNS lookups. And even doing that, you will need to keep up with the actual IP addresses used by the site(s) that you want to block, and also block those IP addresses in a firewall in order to keep users from accessing the site(s) by the IP address(es).