diff --git a/README.md b/README.md
index 6819c03..e446eec 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,8 @@ An nginx module to resolve domain names inside upstreams and keep them up to dat
 
 By default, servers defined in nginx upstreams are only resolved when nginx starts. This module provides an additional `resolve` parameter for `server` definitions that can be used to asynchronously resolve upstream domain names. This keeps the upstream definition up to date according to the DNS TTL of each domain names. This can be useful if you want to use upstreams for dynamic types of domain names that may frequently change IP addresses.
 
+In addition to `resolve`, it allow optional `refresh_interval` to modify default value of 1000 (1s).
+
 This module also allows nginx to start if an upstream contains a defunct domain name that no longer resolves. By default, nginx will fail to start if an upstream server contains an unresolvable domain name. With this module, nginx is still allowed to start with invalid domain names, but an error will be logged and the unresolvable domain names will be marked as down.
 
 ## Installation
@@ -24,7 +26,7 @@ http {
   resolver 8.8.8.8;
 
   upstream example {
-    server example.com resolve;
+    server example.com resolve refresh_interval=1000;
   }
 }
 ```
@@ -49,6 +51,7 @@ The following parameters can be used (see nginx's [server documentation](http://
 `backup`  
 `down`  
 `resolve`  
+`refresh_interval`
 
 # Compatibility
 
diff --git a/ngx_http_upstream_dynamic_servers.c b/ngx_http_upstream_dynamic_servers.c
index 05b2889..396d76a 100644
--- a/ngx_http_upstream_dynamic_servers.c
+++ b/ngx_http_upstream_dynamic_servers.c
@@ -15,6 +15,7 @@ typedef struct {
     ngx_str_t                     host;
     in_port_t                     port;
     ngx_event_t                   timer;
+    ngx_uint_t                    refresh_in;
 } ngx_http_upstream_dynamic_server_conf_t;
 
 typedef struct {
@@ -96,6 +97,8 @@ static char * ngx_http_upstream_dynamic_server_directive(ngx_conf_t *cf, ngx_com
     ngx_int_t                    weight, max_fails;
     ngx_uint_t                   i;
     ngx_http_upstream_server_t  *us;
+    
+   
 
 #if nginx_version <= 1007002
     if (uscf->servers == NULL) {
@@ -193,11 +196,11 @@ static char * ngx_http_upstream_dynamic_server_directive(ngx_conf_t *cf, ngx_com
         }
 
         // BEGIN CUSTOMIZATION: differs from default "server" implementation
-        if (ngx_strcmp(value[i].data, "resolve") == 0) {
+        if (ngx_strcmp(value[i].data, "resolve") == 0){
             // Determine if the server given is an IP address or a hostname by running
             // through ngx_parse_url with no_resolve enabled. Only if a hostname is given
             // will we add this to the list of dynamic servers that we will resolve again.
-
+            
             ngx_memzero(&u, sizeof(ngx_url_t));
             u.url = value[1];
             u.default_port = 80;
@@ -215,10 +218,19 @@ static char * ngx_http_upstream_dynamic_server_directive(ngx_conf_t *cf, ngx_com
 
                 dynamic_server->host = u.host;
                 dynamic_server->port = (in_port_t) (u.no_port ? u.default_port : u.port);
+                dynamic_server->refresh_in = 1000;
+                
             }
 
             continue;
         }
+        
+        // add support for refresh_interval.this must be followed by resolve
+        if (dynamic_server && (ngx_strncmp(value[i].data, "refresh_interval=", 17) == 0)){
+            dynamic_server->refresh_in = ngx_atoi(&value[i].data[17], value[i].len - 17);
+            continue;
+        }
+        
         // END CUSTOMIZATION
 
         goto invalid;
@@ -297,7 +309,7 @@ static void *ngx_http_upstream_dynamic_server_main_conf(ngx_conf_t *cf) {
     }
 
     udsmcf->resolver_timeout = NGX_CONF_UNSET_MSEC;
-
+    
     return udsmcf;
 }
 
@@ -382,6 +394,7 @@ static void ngx_http_upstream_dynamic_server_resolve(ngx_event_t *ev) {
     ctx->timeout = udsmcf->resolver_timeout;
 
     ngx_log_debug(NGX_LOG_DEBUG_CORE, ev->log, 0, "upstream-dynamic-servers: Resolving '%V'", &ctx->name);
+    
     if (ngx_resolve_name(ctx) != NGX_OK) {
         ngx_log_error(NGX_LOG_ALERT, ev->log, 0, "upstream-dynamic-servers: ngx_resolve_name failed for '%V'", &ctx->name);
         ngx_add_timer(&dynamic_server->timer, 1000);
@@ -392,14 +405,15 @@ static void ngx_http_upstream_dynamic_server_resolve_handler(ngx_resolver_ctx_t
     ngx_http_upstream_dynamic_server_main_conf_t  *udsmcf = ngx_http_cycle_get_module_main_conf(ngx_cycle, ngx_http_upstream_dynamic_servers_module);
     ngx_http_upstream_dynamic_server_conf_t *dynamic_server;
     ngx_conf_t cf;
-    uint32_t hash;
     ngx_resolver_node_t  *rn;
     ngx_pool_t *new_pool;
     ngx_addr_t                      *addrs;
+    ngx_uint_t refresh_in = 1000;
 
     dynamic_server = ctx->data;
 
     ngx_log_debug(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0, "upstream-dynamic-servers: Finished resolving '%V'", &ctx->name);
+    
 
     if (ctx->state) {
         ngx_log_error(NGX_LOG_ERR, ctx->resolver->log, 0, "upstream-dynamic-servers: '%V' could not be resolved (%i: %s)", &ctx->name, ctx->state, ngx_resolver_strerror(ctx->state));
@@ -452,6 +466,7 @@ static void ngx_http_upstream_dynamic_server_resolve_handler(ngx_resolver_ctx_t
     }
 
     ngx_log_debug(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0, "upstream-dynamic-servers: No DNS changes for '%V' - keeping existing upstream configuration", &ctx->name);
+    
     goto end;
 
 reinit_upstream:
@@ -463,6 +478,7 @@ static void ngx_http_upstream_dynamic_server_resolve_handler(ngx_resolver_ctx_t
     }
 
     ngx_log_debug(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0, "upstream-dynamic-servers: DNS changes for '%V' detected - reinitializing upstream configuration", &ctx->name);
+    
 
     ngx_memzero(&cf, sizeof(ngx_conf_t));
     cf.name = "dynamic_server_init_upstream";
@@ -510,6 +526,7 @@ static void ngx_http_upstream_dynamic_server_resolve_handler(ngx_resolver_ctx_t
         addr->name.len = len;
         addr->name.data = p;
         ngx_log_debug(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0, "upstream-dynamic-servers: '%V' was resolved to '%V'", &ctx->name, &addr->name);
+        
     }
 
     // If the domain failed to resolve, mark this server as down.
@@ -533,22 +550,21 @@ static void ngx_http_upstream_dynamic_server_resolve_handler(ngx_resolver_ctx_t
     dynamic_server->pool = new_pool;
 
 end:
-
+    if(dynamic_server) {
+       refresh_in = dynamic_server->refresh_in;
+    }
     if (ctx->resolver->log->log_level & NGX_LOG_DEBUG_CORE) {
-        hash = ngx_crc32_short(ctx->name.data, ctx->name.len);
+        uint32_t hash = ngx_crc32_short(ctx->name.data, ctx->name.len);
         rn = ngx_resolver_lookup_name(ctx->resolver, &ctx->name, hash);
-        uint32_t refresh_in;
         if (rn != NULL && rn->ttl) {
-            refresh_in = (rn->valid - ngx_time()) * 1000;
-
-            if (!refresh_in || refresh_in < 1000) {
-                refresh_in = 1000;
+           int32_t  rin = rn->valid - ngx_time();
+            if ( rin > 0) {
+                refresh_in = rin * 1000;
             }
-        } else {
-            refresh_in = 1000;
         }
 
-        ngx_log_debug(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0, "upstream-dynamic-servers: Refreshing DNS of '%V' in %ims", &ctx->name, refresh_in);
+       ngx_log_debug(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0, "upstream-dynamic-servers: Refreshing DNS of '%V' in %ims", &ctx->name, refresh_in);
+       
     }
 
     ngx_resolve_name_done(ctx);
@@ -558,7 +574,7 @@ static void ngx_http_upstream_dynamic_server_resolve_handler(ngx_resolver_ctx_t
         return;
     }
 
-    ngx_add_timer(&dynamic_server->timer, 1000);
+    ngx_add_timer(&dynamic_server->timer, refresh_in);
 }
 
 // Copied from src/core/ngx_resolver.c (nginx version 1.7.7).