android - Simultaneous volley request always returns Server error -

i trying develop android application in hitting server api using volley. have made singleton requestqueue object , sending multiple json request 1 after other. when send first request, receive json object without error. parsing json, extracting ids , again making url , making volley request. time, getting "com.android.volley.servererror". below code:

jsonobjectrequest jreq = new jsonobjectrequest(request.method.get, url, (string) null, new response.listener<jsonobject>() {                     @override                     public void onresponse(jsonobject jsonobject) {                         final volleyparser vp = new volleyparser();                         arraylist<integer> searchids = vp.parsejsonobject(jsonobject, kf, null);                         r.cancelall("saz");                         for(integer id : searchids) {                             final fetch pf = new productfetch();                             string url = pf.searchurl(id.tostring());                              jsonobjectrequest jreqnext = new jsonobjectrequest(request.method.get, url, (string) null, new response.listener<jsonobject>() {                                 @override                                 public void onresponse(jsonobject jsonarray) {                                     log.i("saz", "product rec");                                     vp.parsejsonobject(jsonarray, pf, null);                                 }                             }, new response.errorlistener() {                                 @override                                 public void onerrorresponse(volleyerror volleyerror) {                                     log.i("saz", "pro "+volleyerror.tostring());                                 }                             });                                     /**//*(request.method.post, url, (string) null, new response.listener<jsonobject>() {                                 @override                                 public void onresponse(jsonobject jsonobject) {                                     log.i("saz","product rec");                                     vp.parsejsonobject(jsonobject, pf, null);                                 }                             }, new response.errorlistener() {                                 @override                                 public void onerrorresponse(volleyerror volleyerror) {                                     log.i("saz", volleyerror.tostring());                                 }                             });*/                                     jreqnext.setretrypolicy(new defaultretrypolicy(                                             9000,                                             defaultretrypolicy.default_max_retries,                                             defaultretrypolicy.default_backoff_mult));                              r.add(jreqnext);                      }                 }}, new response.errorlistener() {                     @override                     public void onerrorresponse(volleyerror volleyerror) {                           log.i("saz", "search "+volleyerror.tostring());                     }                 });                 r.add(jreq);         } 

please give more explanation server error looks getting volley server timeout error. please increase request timeout one min , see results. increase timeout yourrequest.setretrypolicy(new defaultretrypolicy(60000, defaultretrypolicy.default_max_retries, defaultretrypolicy.default_backoff_mult));