Hi Vivek,
Does your user have access rights to view the data?
Example for reference (admin user - see aaa_init.xml):
$ pwd
/home/tailf/confd-6.3.1/examples.confd/rest/router
$ diff ./confd.conf /home/tailf/confd-6.3.1/examples.confd/rest/router/confd.conf
266,272d265
< <restconf>
< <enabled>true</enabled>
< <!--
< The RESTCONF root resource is the first part of the RESTCONF API path.
< -->
< <rootResource>restconf</rootResource>
< </restconf>
$ curl -i -u admin:admin http://127.0.0.1:8008/restconf/data/restconf-state -H "Accept: application/yang-data+json" -X GET
HTTP/1.1 200 OK
Server:
Date: Wed, 15 Mar 2017 18:29:32 GMT
Last-Modified: Fri, 01 Jan 1971 00:00:00 GMT
Cache-Control: private, no-cache, must-revalidate, proxy-revalidate
Etag: 1489-602043-233942
Content-Type: application/yang-data+json
Transfer-Encoding: chunked
Pragma: no-cache
{
"ietf-restconf-monitoring:restconf-state": {
"capabilities": {
"capability": ["urn:ietf:params:restconf:capability:defaults:1.0?basic-mode=explicit", "urn:ietf:params:restconf:capability:depth:1.0", "urn:ietf:params:restconf:capability:fields:1.0", "urn:ietf:params:restconf:capability:with-defaults:1.0", "http://tail-f.com/ns/restconf/collection/1.0", "http://tail-f.com/ns/restconf/query-api/1.0"]
}
}
}