This bug was accidentally moved from POST to MODIFIED via an error in automation, please see mmccune with any questions

Additional future.

When one or more ns-slapd are down, the exit value or status-dirsrv shows the number of the down servers.

Example:
There are 3 DS instances are installed.
1) If all are up,
$ status-dirsrv
$ echo $?
0

2) If 2 is down,
$ status-dirsrv
$ echo $?
2

2) If all are down,
$ status-dirsrv
$ echo $?
3

^future^feature^

RFE Verified 
1) [root@test slapd-test]# status-dirsrv 
gave detail information about status of Directory server and Instance 

2) [root@test slapd-test]# status-dirsrv 'instance name'    
gave information about the instance

3) [root@test slapd-test]# man status-dirsrv
show man page for this command

4) Check addition feature mention in comment 5 
give result as mention

As mention in the Man page 
Exit code 255 is returned if the instance does not exist. 
but it return the 2 as exit code

[root@rhel7ds ~]# status-dirsrv rhel7dssfsf
Instance rhel7dssfsf not found.
/usr/sbin/status-dirsrv: line 14: return: -1: invalid option
return: usage: return [n]
[root@rhel7ds ~]# echo $?
2

Can't reproduce the problem.

# status-dirsrv rhel7dssfsf
Instance rhel7dssfsf not found.
# echo $?
255

Could you provide the output of "sh -x status-dirsrv rhel7dssfsf"?
Thanks.

The error comes from bash built-in `return`. bash version prior to 4.3 didn't support negative numbers as argument for `return`.
See for reference: http://wiki.bash-hackers.org/scripting/bashchanges

reproducer.sh:
#!/bin/bash
set -x
main() {
    return -1
}
main
echo $?

On RHEL7 with bash-4.2.46-19.el7.x86_64:
$ bash reproducer.sh 
+ main
+ return -1
reproducer.sh: line 4: return: -1: invalid option
return: usage: return [n]
+ echo 2
2

On Fedora24 with bash-4.3.42-5.fc24.x86_64:
$ bash reproducer.sh
+ main
+ return -1
+ echo 255
255

So in RHEL we need explicitly specify error code 255.

Agh...  Thanks a lot, Viktor!

Bug Verified 
[root@test ~]# status-dirsrv test
● dirsrv - 389 Directory Server test.
   Loaded: loaded (/usr/lib/systemd/system/dirsrv@.service; enabled; vendor preset: disabled)
   Active: active (running) since Mon 2016-07-18 14:16:51 IST; 1h 26min ago
 Main PID: 3836 (ns-slapd)
   Status: "slapd started: Ready to process requests"
   CGroup: /system.slice/system-dirsrv.slice/dirsrv
           └─3836 /usr/sbin/ns-slapd -D /etc/dirsrv/slapd-test -i /var/run/dirsrv/slapd-test.pid

Jul 18 14:16:51 test.example.com systemd[1]: Starting 389 Directory Server test....
Jul 18 14:16:51 test.example.com ns-slapd[3836]: [18/Jul/2016:14:16:51.178734301 +051800] 389-Directory/1.3.5.10 B2016.197.39 starting up
Jul 18 14:16:51 test.example.com ns-slapd[3836]: [18/Jul/2016:14:16:51.572105005 +051800] slapd started.  Listening on All Interfaces port 389 for LDAP requests
Jul 18 14:16:51 test.example.com systemd[1]: Started 389 Directory Server test..
[root@test ~]# echo $?
0
[root@test ~]# status-dirsrv NoInstace
Instance NoInstace not found.
[root@test ~]# echo $?
255

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHSA-2016-2594.html