dns - Am I running NIS? - Ask Ubuntu

i pretty new ubuntu 16, reading

securing , optimizing linux rh edition

and /etc/nsswitch.conf had in

# /etc/nsswitch.conf # # example configuration of gnu name service switch functionality. # if have `glibc-doc-reference' , `info' packages installed, try: # `info libc "name service switch"' information file.  passwd:         compat group:          compat shadow:         compat gshadow:        compat    hosts:          files mdns4_minimal [notfound=return] dns myhostname networks:       files  protocols:      db files services:       db files ethers:         db files rpc:            db files  netgroup:       nis 

so replaced

        hosts:  dns files         passwd:files         shadow:files         group:files         hosts:dns files         bootparams:files         ethers:files         netmasks:files         networks:files         protocols:files         rpc:files         services:files         automount:files         aliases:files            

so question before make permanent how know whether i'm running nis?

/etc/rc.conf empty

you're not running nis, see nisdomainname confirmation:

w3@aardvark:~(0)$ nisdomainname  nisdomainname: local domain name not set w3@aardvark:~(1)$  

nis (network information system, formerly yellow pages) used in corporate network support, , not used anymore.

i question changes on other lines, well. how understand consequences of enduring dns timeouts before can lookup locally stored hostnames (a consequence of hosts: dns files)?

in general, blindly applying recipes "securing , optimizing linux: redhat edition -a hands on guide" ubuntu 16.04.1 cannot expected "work". ubuntu manufactured canonical, red hat linux manufactured red hat. each company configures linux-based product differently.

more generally, blindly applying recipes anywhere not idea. it's worth effort understand you're doing, , you're not shoot in foot.