I'm fail to configure syslog-ng to read the log file from my DD-WRT router. Currently I'm installed syslog-ng on my server and I would like to read the log file from my router which there are in different location, I did try to put my router internet IP address to syslog-ng but I wasn't successful.

not sure what you're getting at. normally, what happens is, you dump the router logs into the syslog server. as such, you need to configure your router's syslog to point to the syslog server.
seems you're trying to get the syslog server to read logs from the router instead? syslog-ng don't do that.

I did giving the remote server in dd-wrt. seem the dd-wrt syslog doesn't send any log to my syslog-ng server. I'm not sure what configuration I miss.

ok, is the server behind a NAT? as in, can the router reach the server(ping)? did you allow the syslog port on the server-side firewall(internal/external)?

Now my router are able to send the log to syslog-ng. May I know what software/script are able to view the logs?

what was the problem?

to read the logs would depend on the syslog-ng config. i don't remember the default config, but syslog should put the logs into a directory somewhere in /var/log. you can filter the content by using hostname, IP, date blabla(in syslog-ng.conf). this is basically the "all manual way".

you can also dump the log into an sql database and use php-syslog-ng as the web front end. much easier to read.