Fresh Installation on centos 7 giving error

Traceback (most recent call last):
File “/bin/bench”, line 11, in
load_entry_point(‘bench’, ‘console_scripts’, ‘bench’)()
File “/opt/bench/bench-repo/bench/cli.py”, line 40, in cli
bench_command()
File “/usr/lib/python2.7/site-packages/click/core.py”, line 764, in call
return self.main(*args, **kwargs)
File “/usr/lib/python2.7/site-packages/click/core.py”, line 717, in main
rv = self.invoke(ctx)
File “/usr/lib/python2.7/site-packages/click/core.py”, line 1137, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File “/usr/lib/python2.7/site-packages/click/core.py”, line 1137, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File “/usr/lib/python2.7/site-packages/click/core.py”, line 956, in invoke
return ctx.invoke(self.callback, **ctx.params)
File “/usr/lib/python2.7/site-packages/click/core.py”, line 555, in invoke
return callback(*args, **kwargs)
File “/opt/bench/bench-repo/bench/commands/setup.py”, line 41, in setup_redis
generate_config(‘.’)
File “/opt/bench/bench-repo/bench/config/redis.py”, line 15, in generate_config
ports[key] = urlparse(config[key]).port
KeyError: ‘redis_cache’

I followed this article and installed everything required

then logged in to bench via ssh putty

than tried to run
bench init erpnext && cd erpnext

to install erpnext but got error as mentioned above