Verify the server socket in cjdroute is open:
$ netstat -l |grep 11234
tcp 0 0 localhost:11234 *:* LISTEN
Start the server:
/cjdns$ build/admin/http/HttpServer 127.0.0.1:11234 `pwd`/admin/http/
Verify it bound to a port:
$ netstat -l |grep 51902