diff --git a/src/or/or.h b/src/or/or.h
index dee1881034..d9be1be37d 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -793,6 +793,11 @@ typedef struct rend_data_t {
   /** Onion address (without the .onion part) that a client requests. */
   char onion_address[REND_SERVICE_ID_LEN_BASE32+1];
 
+  /** Descriptor ID for each replicas computed from the onion address. If
+   * the onion address is empty, this array MUST be empty. We keep them so
+   * we know when to purge our entry in the last hsdir request table. */
+  char descriptor_id[REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS][DIGEST_LEN];
+
   /** (Optional) descriptor cookie that is used by a client. */
   char descriptor_cookie[REND_DESC_COOKIE_LEN];
 
@@ -800,8 +805,9 @@ typedef struct rend_data_t {
   rend_auth_type_t auth_type;
 
   /** Descriptor ID for a client request. The control port command HSFETCH
-   * can use this. */
-  char descriptor_id[DIGEST_LEN];
+   * uses this. It's set if the descriptor query should only use this
+   * descriptor ID. */
+  char desc_id_fetch[DIGEST_LEN];
 
   /** Hash of the hidden service's PK used by a service. */
   char rend_pk_digest[DIGEST_LEN];
diff --git a/src/or/rendclient.c b/src/or/rendclient.c
index 13781c212e..8a8d8f7243 100644
--- a/src/or/rendclient.c
+++ b/src/or/rendclient.c
@@ -860,8 +860,8 @@ rend_client_fetch_v2_desc(const rend_data_t *query,
 
   if (query->onion_address[0] != '\0') {
     ret = fetch_v2_desc_by_addr(query, hsdirs);
-  } else if (query->descriptor_id[0] != '\0') {
-    ret = fetch_v2_desc_by_descid(query->descriptor_id, query, hsdirs);
+  } else if (!tor_digest_is_zero(query->desc_id_fetch)) {
+    ret = fetch_v2_desc_by_descid(query->desc_id_fetch, query, hsdirs);
   } else {
     /* Query data is invalid. */
     ret = -1;
diff --git a/src/or/rendcommon.c b/src/or/rendcommon.c
index 03dd757921..1b042f9fe9 100644
--- a/src/or/rendcommon.c
+++ b/src/or/rendcommon.c
@@ -1404,3 +1404,100 @@ rend_data_dup(const rend_data_t *data)
   return tor_memdup(data, sizeof(rend_data_t));
 }
 
+/** Compute descriptor ID for each replicas and save them. A valid onion
+ * address must be present in the <b>rend_data</b>.
+ *
+ * Return 0 on success else -1. */
+static int
+compute_desc_id(rend_data_t *rend_data)
+{
+  int ret, replica;
+  time_t now = time(NULL);
+
+  tor_assert(rend_data);
+
+  /* Compute descriptor ID for each replicas. */
+  for (replica = 0; replica < ARRAY_LENGTH(rend_data->descriptor_id);
+       replica++) {
+    ret = rend_compute_v2_desc_id(rend_data->descriptor_id[replica],
+                                  rend_data->onion_address,
+                                  rend_data->descriptor_cookie,
+                                  now, replica);
+    if (ret < 0) {
+      goto end;
+    }
+  }
+
+end:
+  return ret;
+}
+
+/** Allocate and initialize a rend_data_t object for a service using the
+ * given arguments. Only the <b>onion_address</b> is not optional.
+ *
+ * Return a valid rend_data_t pointer. */
+rend_data_t *
+rend_data_service_create(const char *onion_address, const char *pk_digest,
+                         const uint8_t *cookie, rend_auth_type_t auth_type)
+{
+  rend_data_t *rend_data = tor_malloc_zero(sizeof(*rend_data));
+
+  /* We need at least one else the call is wrong. */
+  tor_assert(onion_address != NULL);
+
+  if (pk_digest) {
+    memcpy(rend_data->rend_pk_digest, pk_digest,
+           sizeof(rend_data->rend_pk_digest));
+  }
+  if (cookie) {
+    memcpy(rend_data->rend_cookie, cookie,
+           sizeof(rend_data->rend_cookie));
+  }
+
+  strlcpy(rend_data->onion_address, onion_address,
+          sizeof(rend_data->onion_address));
+  rend_data->auth_type = auth_type;
+
+  return rend_data;
+}
+
+/** Allocate and initialize a rend_data_t object for a client request using
+ * the given arguments.  Either an onion address or a descriptor ID is
+ * needed. Both can be given but only the onion address will be used to make
+ * the descriptor fetch.
+ *
+ * Return a valid rend_data_t pointer or NULL on error meaning the
+ * descriptor IDs couldn't be computed from the given data. */
+rend_data_t *
+rend_data_client_create(const char *onion_address, const char *desc_id,
+                        const char *cookie, rend_auth_type_t auth_type)
+{
+  rend_data_t *rend_data = tor_malloc_zero(sizeof(*rend_data));
+
+  /* We need at least one else the call is wrong. */
+  tor_assert(onion_address != NULL || desc_id != NULL);
+
+  if (cookie) {
+    memcpy(rend_data->descriptor_cookie, cookie,
+           sizeof(rend_data->descriptor_cookie));
+  }
+  if (desc_id) {
+    memcpy(rend_data->desc_id_fetch, desc_id,
+           sizeof(rend_data->desc_id_fetch));
+  }
+  if (onion_address) {
+    strlcpy(rend_data->onion_address, onion_address,
+            sizeof(rend_data->onion_address));
+    if (compute_desc_id(rend_data) < 0) {
+      goto error;
+    }
+  }
+
+  rend_data->auth_type = auth_type;
+
+  return rend_data;
+
+error:
+  rend_data_free(rend_data);
+  return NULL;
+}
diff --git a/src/or/rendcommon.h b/src/or/rendcommon.h
index b86cdb7fa6..a4d55d21d0 100644
--- a/src/or/rendcommon.h
+++ b/src/or/rendcommon.h
@@ -67,5 +67,13 @@ void rend_get_descriptor_id_bytes(char *descriptor_id_out,
                                   const char *secret_id_part);
 size_t rend_cache_get_total_allocation(void);
 
+rend_data_t *rend_data_client_create(const char *onion_address,
+                                     const char *desc_id,
+                                     const char *cookie,
+                                     rend_auth_type_t auth_type);
+rend_data_t *rend_data_service_create(const char *onion_address,
+                                      const char *pk_digest,
+                                      const uint8_t *cookie,
+                                      rend_auth_type_t auth_type);
 #endif