They do not work because the second server is only queried if the query of the first one returns with an error. An error is something like a timeout, an answer from the DNS server that the address/name is not know is not an error but a valid DNS answer.
Since you already have a DNS server in your network at 192.168.1.254 you should configure that one to use 8.8.8.8 as upstream server, so that your local DNS server can forward the DNS queries that are out of the local scope.
On your clients, just use 192.168.1.254 as DNS server and you are done.
To find the DNS server that is running at 192.168.1.254, you could run the command as follows.
lsof -n -i:53Now identify the DNS server binary and lookup the manpage to configure the upstream server.
