Failure in source install kong 0.14.1

Installation/Setup
1

Hi ,

Facing an issue while starting kong.

$- kong start
root@ip-172-31-15-170:/usr/local/lib/luarocks/rocks-5.1# kong start 
2018/09/11 19:47:29 [warn] ulimit is currently set to "1024". For better performance set it to at least "4096" using "ulimit -n"
Error: /usr/local/share/lua/5.1/kong/cmd/start.lua:28: nginx configuration is invalid (exit code 1):
nginx: the configuration file /usr/local/kong/nginx.conf syntax is ok
nginx: [error] init_by_lua error: /usr/local/share/lua/5.1/luarocks/core/cfg.lua:729: attempt to index a nil value
stack traceback:
        /usr/local/share/lua/5.1/luarocks/core/cfg.lua:729: in function 'init'
        /usr/local/share/lua/5.1/luarocks/loader.lua:19: in main chunk
        [C]: in function 'require'
        /usr/local/share/lua/5.1/kong/init.lua:27: in main chunk
        [C]: in function 'require'
        init_by_lua:2: in main chunk
nginx: configuration file /usr/local/kong/nginx.conf test failed

OS: ubuntu 14.04
Kong version trying to install - 0.14.1
Followed installation instructions from - https://docs.konghq.com/install/source/

Few deviations I have done during the install -
Instead of compiling openresty, I’ve used the pre-build package for ubuntu
Instead of doing a git clone of the kong project, I’ve downloaded and extracted the tar file for 0.14.1 from github