Private servers?

Any1 knows how to play on private servers. I have the game but it always give me issues...

go on google and search for call of duty 4 cracked servers, something like private-servers will appear look at the ips on there copy a server you wanna go on then go on cod 4 go on option enable console or make sure its enabled then press ` then enter connect "ip" example connect 324.234.245.234:2899 that ip is a random ip