Mandar if you just create server and expect people to even see it then its not gona happen.
You need to configure the ports.
Configure your net settings for server to be listed on steam browser and visible to others.
If you are not getting anyone it means your server is not visible to others.
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You need these ports opened from windows firewall or any other firewall that you are using. or you need to forword it to the router in case you use router.
UDP 1200 (Friends Network)
UDP 27000 to 27015 (Gameport)
UDP 27020
TCP 27030 to 27039
TCP: 27015 (SRCDS Rcon port)
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If you are on the local WAN cable setup like sify, pacenet, aquira, exattnet then you also need to add your external ip to the ip list.
for that once you are connected to net, go to following site.
*www.ostrosoft.com/OIT/external_ip.asp
that will give you your external ip.
then go to control pannel>network connections> right click on your LAN adaptor and click on properties.
It will open a new window. there click on Internet Protocol and then click on properties.
In the new window you will have your ip settings. Click advanced.
In the IP address window click add. and enter your external ip address there and click ok.
You have to do this every time you connect to the net. Delete old entry and add new.
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Now you are good to go. Your server should be visible on the steam network and if pings are good then you will get people on your server.
I am hosting CSS server for quiet a while and i do get many people playing on it.
For any assistance go to steam powered forums.
Read this thread. Its for CSS but all IP/firewall setings for CSS and HL2 DM are same.
*forums.steampowered.com/forums/showthread.php?s=&threadid=189717
Hope this helps you.