Merge pull request etcd-io#15041 from ahrtr/update_nsswitch_3.5

[3.5] Update nsswitch.conf for 3.5

nsswitch.conf

@@ -1,2 +1,22 @@
+# /etc/nsswitch.conf
+#
+# Example configuration of GNU Name Service Switch functionality.
+# If you have the `glibc-doc-reference' and `info' packages installed, try:
+# `info libc "Name Service Switch"' for information about this file.
+
+passwd:         compat
+group:          compat
+shadow:         compat
+gshadow:        files
+
+hosts:          files dns
+networks:       files
+
+protocols:      db files
+services:       db files
+ethers:         db files
+rpc:            db files
+
+netgroup:       nis
 hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4