I see that the serial of the reverse zone is 1997022700. Have you increased it after the changes you've done? Also you use as NS the localhost. Is it the same box, with the one with the 10.16.126.1 IP?
And what is your domain? Is it s170switch?
Try this and see if it works:
@ IN SOA localhost. root.localhost. (
2010052101 ; Serial
28800 ; Refresh
14400 ; Retry
3600000 ; Expire
86400 ) ; Minimum
IN NS <host-with-10.16.126.1>
10 IN PTR s60-naga.s170switch.
11 IN PTR s60-guru.s170switch.
12 IN PTR s60-hari.s170switch.
Regarding the forward zone you don't have an A record for the NS (s170switch). You need something like:
IN NS s170switch.
s170switch. IN A 192.168.127.10
Don't forget to increase the serial before reloading named!!