--- httpd-2.4.29/modules/proxy/mod_proxy.c	2017-10-13 09:30:15.000000000 +0200
+++ httpd-2.4.29/modules/proxy/mod_proxy.c	2017-11-20 16:22:25.199425973 +0100
@@ -129,6 +129,16 @@ 
             return "TTL must be at least one second";
         worker->s->ttl = apr_time_from_sec(ival);
     }
+    else if (!strcasecmp(key, "dnsttl")) {
+    	 /* Time in seconds that will cause a new dns lookup
+    	  * for the connection
+    	  */
+    	ival = atoi(val);
+    	if (ival < 1) {
+    		return "DNSTTL must be at least one second";
+    	}
+    	worker->s->dns_ttl = apr_time_from_sec(ival);
+    }
     else if (!strcasecmp(key, "min")) {
         /* Initial number of connections to remote
          */
--- httpd-2.4.29/modules/proxy/mod_proxy.h	2017-08-18 10:49:42.000000000 +0200
+++ httpd-2.4.29/modules/proxy/mod_proxy.h	2017-11-20 16:23:02.511427302 +0100
@@ -285,6 +285,7 @@ 
 
 /* Connection pool */
 struct proxy_conn_pool {
+    apr_time_t      updated;    /* timestamp of last update */
     apr_pool_t     *pool;   /* The pool used in constructor and destructor calls */
     apr_sockaddr_t *addr;   /* Preparsed remote address info */
     apr_reslist_t  *res;    /* Connection resource list */
@@ -414,6 +415,7 @@ 
     apr_interval_time_t acquire; /* acquire timeout when the maximum number of connections is exceeded */
     apr_interval_time_t ping_timeout;
     apr_interval_time_t conn_timeout;
+    apr_interval_time_t dns_ttl;	/* TTL for a stored DNS ip address to be looked up again */
     apr_size_t      recv_buffer_size;
     apr_size_t      io_buffer_size;
     apr_size_t      elected;    /* Number of times the worker was elected */
--- httpd-2.4.29/modules/proxy/proxy_util.c	2017-09-19 12:17:40.000000000 +0200
+++ httpd-2.4.29/modules/proxy/proxy_util.c	2017-11-20 16:35:45.607454477 +0100
@@ -2337,13 +2337,30 @@ 
                                             conn->hostname, APR_UNSPEC,
                                             conn->port, 0,
                                             worker->cp->pool);
+                worker->cp->updated = apr_time_now();
                 conn->addr = worker->cp->addr;
                 if ((uerr = PROXY_THREAD_UNLOCK(worker)) != APR_SUCCESS) {
                     ap_log_rerror(APLOG_MARK, APLOG_ERR, uerr, r, APLOGNO(00946) "unlock");
                 }
             }
             else {
-                conn->addr = worker->cp->addr;
+            	/* cp pool has been created once + dns_ttl is set + dns ttl expired */
+            	if ( worker->cp->updated && worker->s->dns_ttl && \
+            			( worker->s->dns_ttl < ( apr_time_now() - worker->cp->updated ) ) ) {
+                    worker->cp->updated = apr_time_now();
+                    /* work in current conn directly */
+                    err = apr_sockaddr_info_get(&(conn->addr),
+                                                conn->hostname, APR_UNSPEC,
+                                                conn->port, 0,
+                                                conn->pool);
+                    /* save in cp if different */
+                    if (! apr_sockaddr_equal(worker->cp->addr, conn->addr) ) {
+                    	apr_sockaddr_info_copy(&(worker->cp->addr), conn->addr, worker->cp->pool);
+                    }
+            	}
+            	else {
+            		conn->addr = worker->cp->addr;
+            	}
             }
         }
     }