From: Kern Sibbald <kern@sibbald.com>
Date: Sun, 23 Sep 2007 18:49:57 +0000 (+0000)
Subject: kes  Rework the reservation system to take into account that the Director
X-Git-Tag: Release-7.0.0~5628
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=0cd0316e40d0ad454b2958c7b6f9c1f27095c843;p=bacula%2Fbacula

kes  Rework the reservation system to take into account that the Director
     might give us a Volume that is different from the current one being
     used, and to ensure that we don't exceed Maximum Volume Jobs.
     This fixes (mostly) bug #947 '  Maximum Volume Jobs = 1 produces
     fatal error with multiple jobs running'
kes  Add more debug code in reservation system.
kes  Implement maxvol-test to check bug #947.

git-svn-id: https://bacula.svn.sourceforge.net/svnroot/bacula/trunk@5630 91ce42f0-d328-0410-95d8-f526ca767f89
---

diff --git a/bacula/src/dird/next_vol.c b/bacula/src/dird/next_vol.c
index 40722bef87..6aecf5331d 100644
--- a/bacula/src/dird/next_vol.c
+++ b/bacula/src/dird/next_vol.c
@@ -57,7 +57,8 @@ int find_next_volume_for_append(JCR *jcr, MEDIA_DBR *mr, int index,
    STORE *store = jcr->wstore;
 
    bstrncpy(mr->MediaType, store->media_type, sizeof(mr->MediaType));
-   Dmsg2(150, "find_next_vol_for_append: PoolId=%d, MediaType=%s\n", (int)mr->PoolId, mr->MediaType);
+   Dmsg3(100, "find_next_vol_for_append: JobId=%u PoolId=%d, MediaType=%s\n", 
+         (uint32_t)jcr->JobId, (int)mr->PoolId, mr->MediaType);
    /*
     * If we are using an Autochanger, restrict Volume
     *   search to the Autochanger on the first pass
@@ -209,6 +210,8 @@ bool has_volume_expired(JCR *jcr, MEDIA_DBR *mr)
       } else if (mr->MaxVolJobs > 0 && mr->MaxVolJobs <= mr->VolJobs) {
          Jmsg(jcr, M_INFO, 0, _("Max Volume jobs exceeded. "
              "Marking Volume \"%s\" as Used.\n"), mr->VolumeName);
+         Dmsg3(100, "MaxVolJobs=%d JobId=%d Vol=%s\n", mr->MaxVolJobs,
+               (uint32_t)jcr->JobId, mr->VolumeName);
          bstrncpy(mr->VolStatus, "Used", sizeof(mr->VolStatus));
          expired = true;
 
diff --git a/bacula/src/lib/jcr.c b/bacula/src/lib/jcr.c
index 0835c36a30..a56eb332cc 100644
--- a/bacula/src/lib/jcr.c
+++ b/bacula/src/lib/jcr.c
@@ -601,7 +601,8 @@ void set_jcr_job_status(JCR *jcr, int JobStatus)
     * For a set of errors, ... keep the current status
     *   so it isn't lost. For all others, set it.
     */
-   Dmsg2(100, "OnEntry JobStatus=%c set=%c\n", jcr->JobStatus, JobStatus);
+   Dmsg3(300, "jid=%u OnEntry JobStatus=%c set=%c\n", (uint32_t)jcr->JobId,
+         jcr->JobStatus, JobStatus);
    switch (jcr->JobStatus) {
    case JS_ErrorTerminated:
    case JS_FatalError:
@@ -621,7 +622,8 @@ void set_jcr_job_status(JCR *jcr, int JobStatus)
    default:
       jcr->JobStatus = JobStatus;
    }
-   Dmsg2(100, "OnExit JobStatus=%c set=%c\n", jcr->JobStatus, JobStatus);
+   Dmsg3(100, "jid=%u OnExit JobStatus=%c set=%c\n", (uint32_t)jcr->JobId,
+         jcr->JobStatus, JobStatus);
 }
 
 #ifdef TRACE_JCR_CHAIN
diff --git a/bacula/src/stored/acquire.c b/bacula/src/stored/acquire.c
index 9bb22a7809..31f81d8adc 100644
--- a/bacula/src/stored/acquire.c
+++ b/bacula/src/stored/acquire.c
@@ -445,7 +445,8 @@ DCR *acquire_device_for_append(DCR *dcr)
    dev->dlock();
    if (dcr->reserved_device) {
       dev->reserved_device--;
-      Dmsg2(100, "Dec reserve=%d dev=%s\n", dev->reserved_device, dev->print_name());
+      Dmsg3(100, "jid=%u Dec reserve=%d dev=%s\n", (uint32_t)jcr->JobId,
+            dev->reserved_device, dev->print_name());
       dcr->reserved_device = false;
    }
    dev->dunblock(DEV_LOCKED);
@@ -458,7 +459,8 @@ get_out:
    dev->dlock();
    if (dcr->reserved_device) {
       dev->reserved_device--;
-      Dmsg2(100, "Dec reserve=%d dev=%s\n", dev->reserved_device, dev->print_name());
+      Dmsg3(100, "jid=%u Dec reserve=%d dev=%s\n", (uint32_t)jcr->JobId, 
+            dev->reserved_device, dev->print_name());
       dcr->reserved_device = false;
    }
    dev->dunblock(DEV_LOCKED);
diff --git a/bacula/src/stored/askdir.c b/bacula/src/stored/askdir.c
index e533d76f83..c3c448f872 100644
--- a/bacula/src/stored/askdir.c
+++ b/bacula/src/stored/askdir.c
@@ -179,7 +179,7 @@ static bool do_get_volume_info(DCR *dcr)
        return false;
     }
     memset(&vol, 0, sizeof(vol));
-    Dmsg1(100, "<dird %s\n", dir->msg);
+    Dmsg2(100, "<dird jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
     n = sscanf(dir->msg, OK_media, vol.VolCatName,
                &vol.VolCatJobs, &vol.VolCatFiles,
                &vol.VolCatBlocks, &vol.VolCatBytes,
@@ -191,7 +191,8 @@ static bool do_get_volume_info(DCR *dcr)
                &vol.EndFile, &vol.EndBlock, &vol.VolCatParts,
                &vol.LabelType, &vol.VolMediaId);
     if (n != 22) {
-       Dmsg3(100, "Bad response from Dir fields=%d, len=%d: %s", n, dir->msglen, dir->msg);
+       Dmsg4(100, "Bad response from Dir jid=%u fields=%d, len=%d: %s", 
+             (uint32_t)jcr->JobId, n, dir->msglen, dir->msg);
        Mmsg(jcr->errmsg, _("Error getting Volume info: %s"), dir->msg);
        return false;
     }
@@ -200,8 +201,8 @@ static bool do_get_volume_info(DCR *dcr)
     bstrncpy(dcr->VolumeName, vol.VolCatName, sizeof(dcr->VolumeName));
     dcr->VolCatInfo = vol;            /* structure assignment */
 
-    Dmsg2(100, "do_reqest_vol_info return true slot=%d Volume=%s\n",
-          vol.Slot, vol.VolCatName);
+    Dmsg3(100, "do_reqest_vol_info return true jid=%u slot=%d Volume=%s\n",
+          (uint32_t)jcr->JobId, vol.Slot, vol.VolCatName);
     return true;
 }
 
@@ -226,7 +227,7 @@ bool dir_get_volume_info(DCR *dcr, enum get_vol_info_rw writing)
     bash_spaces(dcr->VolCatInfo.VolCatName);
     dir->fsend(Get_Vol_Info, jcr->Job, dcr->VolCatInfo.VolCatName,
        writing==GET_VOL_INFO_FOR_WRITE?1:0);
-    Dmsg1(100, ">dird: %s\n", dir->msg);
+    Dmsg2(100, ">dird jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
     unbash_spaces(dcr->VolCatInfo.VolCatName);
     bool ok = do_get_volume_info(dcr);
     V(vol_info_mutex);
@@ -268,14 +269,14 @@ bool dir_find_next_appendable_volume(DCR *dcr)
        dir->fsend(Find_media, jcr->Job, vol_index, dcr->pool_name, dcr->media_type);
        unbash_spaces(dcr->media_type);
        unbash_spaces(dcr->pool_name);
-       Dmsg1(100, ">dird: %s", dir->msg);
+       Dmsg2(100, ">dird jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
        bool ok = do_get_volume_info(dcr);
        if (ok) {
           if (!is_volume_in_use(dcr)) {
              found = true;
              break;
           } else {
-             Dmsg1(100, "Volume %s is in use.\n", dcr->VolumeName);
+             Dmsg2(100, "jid=%u Volume %s is in use.\n", (uint32_t)jcr->JobId, dcr->VolumeName);
              dcr->volume_in_use = true;
              continue;
           }
@@ -355,7 +356,7 @@ bool dir_update_volume_info(DCR *dcr, bool label)
       edit_int64(vol->VolWriteTime, ed4),
       edit_uint64(vol->VolFirstWritten, ed5),
       vol->VolCatParts);
-    Dmsg1(100, ">dird: %s", dir->msg);
+    Dmsg2(100, ">dird jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
 
    /* Do not lock device here because it may be locked from label */
    if (!do_get_volume_info(dcr)) {
@@ -364,7 +365,7 @@ bool dir_update_volume_info(DCR *dcr, bool label)
          vol->VolCatName, jcr->errmsg);
       goto bail_out;
    }
-   Dmsg1(420, "get_volume_info(): %s", dir->msg);
+   Dmsg2(420, "get_volume_info() jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
    /* Update dev Volume info in case something changed (e.g. expired) */
    dev->VolCatInfo = dcr->VolCatInfo;
    ok = true;
@@ -399,14 +400,14 @@ bool dir_create_jobmedia_record(DCR *dcr)
       dcr->StartBlock, dcr->EndBlock, 
       dcr->Copy, dcr->Stripe, 
       edit_uint64(dcr->VolMediaId, ed1));
-    Dmsg1(100, ">dird: %s", dir->msg);
+    Dmsg2(100, ">dird jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
    if (bnet_recv(dir) <= 0) {
       Dmsg0(190, "create_jobmedia error bnet_recv\n");
       Jmsg(jcr, M_FATAL, 0, _("Error creating JobMedia record: ERR=%s\n"),
            bnet_strerror(dir));
       return false;
    }
-   Dmsg1(100, "<dir: %s", dir->msg);
+   Dmsg2(100, "<dird jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
    if (strcmp(dir->msg, OK_create) != 0) {
       Dmsg1(130, "Bad response from Dir: %s\n", dir->msg);
       Jmsg(jcr, M_FATAL, 0, _("Error creating JobMedia record: %s\n"), dir->msg);
@@ -440,7 +441,7 @@ bool dir_update_file_attributes(DCR *dcr, DEV_RECORD *rec)
    ser_uint32(rec->data_len);
    ser_bytes(rec->data, rec->data_len);
    dir->msglen = ser_length(dir->msg);
-   Dmsg1(1800, ">dird: %s\n", dir->msg);    /* Attributes */
+   Dmsg2(1800, ">dird jid=%u: %s\n", (uint32_t)jcr->JobId, dir->msg);    /* Attributes */
    return bnet_send(dir);
 }
 
diff --git a/bacula/src/stored/job.c b/bacula/src/stored/job.c
index 32cf344193..1002c04f40 100644
--- a/bacula/src/stored/job.c
+++ b/bacula/src/stored/job.c
@@ -137,9 +137,9 @@ bool job_cmd(JCR *jcr)
    make_session_key(auth_key, NULL, 1);
    dir->fsend(OKjob, jcr->VolSessionId, jcr->VolSessionTime, auth_key);
    if (debug_level == 3) {
-      Dmsg1(000, ">dird: %s", dir->msg);
+      Dmsg2(000, ">dird jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
    }
-   Dmsg1(100, ">dird: %s", dir->msg);
+   Dmsg2(100, ">dird jid=%u: %s", (uint32_t)jcr->JobId, dir->msg);
    jcr->sd_auth_key = bstrdup(auth_key);
    memset(auth_key, 0, sizeof(auth_key));
    generate_daemon_event(jcr, "JobStart");
@@ -189,7 +189,7 @@ bool run_cmd(JCR *jcr)
    V(mutex);
 
    if (debug_level == 3) {
-      Dmsg0(000, "Zap sd_auth_key\n");
+      Dmsg1(000, "jid=%u Zap sd_auth_key\n", (uint32_t)jcr->JobId);
    }
    memset(jcr->sd_auth_key, 0, strlen(jcr->sd_auth_key));
 
@@ -231,14 +231,14 @@ void handle_filed_connection(BSOCK *fd, char *job_name)
     * Authenticate the File daemon
     */
    if (debug_level == 3) {
-      Dmsg1(000, "sd_auth_key=%s\n", jcr->sd_auth_key);
+      Dmsg2(000, "jid=%u sd_auth_key=%s\n", (uint32_t)jcr->JobId, jcr->sd_auth_key);
    }
    if (jcr->authenticated || !authenticate_filed(jcr)) {
       Dmsg1(100, "Authentication failed Job %s\n", jcr->Job);
       Jmsg(jcr, M_FATAL, 0, _("Unable to authenticate File daemon\n"));
    } else {
       jcr->authenticated = true;
-      Dmsg1(110, "OK Authentication Job %s\n", jcr->Job);
+      Dmsg2(110, "OK Authentication jid=%u Job %s\n", (uint32_t)jcr->JobId, jcr->Job);
    }
 
    if (!jcr->authenticated) {
diff --git a/bacula/src/stored/lock.c b/bacula/src/stored/lock.c
index 9b2a4ca1f8..a52ff4e5e3 100644
--- a/bacula/src/stored/lock.c
+++ b/bacula/src/stored/lock.c
@@ -88,6 +88,15 @@ const int dbglvl = 500;
  *   DEVICE::dlock()   does P(m_mutex)     (in dev.h)
  *   DEVICE::dunlock() does V(m_mutex)
  *
+ *   DEVICE::r_dlock() does recursive locking
+ *                    dlock()
+ *                    if blocked and not same thread that locked
+ *                       pthread_cond_wait
+ *                    leaves device locked 
+ *
+ *   DEVICE::r_dunlock()
+ *                    same as dunlock();
+ *
  *   DEVICE::dblock(why)  does 
  *                    r_dlock();         (recursive device lock)
  *                    block_device(this, why) 
@@ -98,15 +107,6 @@ const int dbglvl = 500;
  *                    unblock_device()
  *                    dunlock()
  *
- *   DEVICE::r_dlock() does recursive locking
- *                    dlock()
- *                    if blocked and not same thread that locked
- *                       pthread_cond_wait
- *                    leaves device locked 
- *
- *   DEVICE::r_dunlock()
- *                    same as dunlock();
- *
  *   block_device() does  (must be locked and not blocked at entry)  
  *                    set blocked status
  *                    set our pid
diff --git a/bacula/src/stored/mount.c b/bacula/src/stored/mount.c
index 0b91ce6b74..8eb2f3f91b 100644
--- a/bacula/src/stored/mount.c
+++ b/bacula/src/stored/mount.c
@@ -588,6 +588,7 @@ void release_volume(DCR *dcr)
    /*
     * First erase all memory of the current volume
     */
+   free_volume(dev);
    dev->block_num = dev->file = 0;
    dev->EndBlock = dev->EndFile = 0;
    memset(&dev->VolCatInfo, 0, sizeof(dev->VolCatInfo));
diff --git a/bacula/src/stored/reserve.c b/bacula/src/stored/reserve.c
index 349aa29592..745e176068 100644
--- a/bacula/src/stored/reserve.c
+++ b/bacula/src/stored/reserve.c
@@ -39,7 +39,7 @@
 #include "bacula.h"
 #include "stored.h"
 
-#define jid() ((int)get_jobid_from_tid())
+#define jid() ((uint32_t)get_jobid_from_tid())
 
 const int dbglvl =  50;
 
@@ -185,7 +185,7 @@ static void debug_list_volumes(const char *imsg)
    DEVICE *dev = NULL;
    foreach_dlist(vol, vol_list) {
       if (vol->dev == dev) {
-         Dmsg0(000, "Two Volumes on same device.\n");
+         Dmsg0(dbglvl, "Two Volumes on same device.\n");
          ASSERT(0);
          dev = vol->dev;
       }
@@ -292,11 +292,11 @@ static void free_vol_item(VOLRES *vol)
  *  already exist and are correctly programmed and will need no changes -- use 
  *  counts are always very tricky.
  *
- *  The old code had a concept of "reserving" a Volume, but it needs to be changed 
+ *  The old code had a concept of "reserving" a Volume, but was changed 
  *  to reserving and using a drive.  A volume is must be attached to (owned by) a 
  *  drive and can move from drive to drive or be unused given certain specific 
  *  conditions of the drive.  The key is that the drive must "own" the Volume.  
- *  The old code has the job (dcr) owning the volume (more or less).  The job is 
+ *  The old code had the job (dcr) owning the volume (more or less).  The job was
  *  to change the insertion and removal of the volumes from the list to be based 
  *  on the drive rather than the job.  
  *
@@ -331,6 +331,10 @@ VOLRES *reserve_volume(DCR *dcr, const char *VolumeName)
       if (strcmp(vol->vol_name, VolumeName) == 0) {
          goto get_out;                  /* Volume already on this device */
       } else {
+         if (dev->is_busy() && dev->VolHdr.VolumeName[0]) {
+            vol = NULL;
+            goto get_out;
+         }
          Dmsg3(dbglvl, "jid=%u reserve_vol free vol=%s at %p\n", 
                (int)dcr->jcr->JobId, vol->vol_name, vol->vol_name);
          debug_list_volumes("reserve_vol free");
@@ -837,6 +841,7 @@ bool find_suitable_device_for_job(JCR *jcr, RCTX &rctx)
       dlist *temp_vol_list, *save_vol_list;
       VOLRES *vol = NULL;
       lock_volumes();
+      Dmsg1(dbglvl, "jid=%u lock volumes\n", (uint32_t)rctx.jcr->JobId);
 
       /*  
        * Create a temporary copy of the volume list.  We do this,
@@ -863,6 +868,7 @@ bool find_suitable_device_for_job(JCR *jcr, RCTX &rctx)
             Jmsg(jcr, M_WARNING, 0, "Logic error. Duplicating vol list hit duplicate.\n");
          }
       }
+      Dmsg1(dbglvl, "jid=%u unlock volumes\n", (uint32_t)jcr->JobId);
       unlock_volumes();
 
       /* Look through reserved volumes for one we can use */
@@ -928,12 +934,14 @@ bool find_suitable_device_for_job(JCR *jcr, RCTX &rctx)
          }
       } /* end for loop over reserved volumes */
 
+      Dmsg1(dbglvl, "jid=%u lock volumes\n", (uint32_t)rctx.jcr->JobId);
       lock_volumes();
       save_vol_list = vol_list;
       vol_list = temp_vol_list;
       free_volume_list();                  /* release temp_vol_list */
       vol_list = save_vol_list;
       Dmsg1(dbglvl, "jid=%u deleted temp vol list\n", (int)rctx.jcr->JobId);
+      Dmsg1(dbglvl, "jid=%u lock volumes\n", (uint32_t)rctx.jcr->JobId);
       unlock_volumes();
    }
    if (ok) {
@@ -1122,6 +1130,15 @@ static int reserve_device(RCTX &rctx)
              */
             if (dcr->volume_in_use && !rctx.PreferMountedVols) {
                rctx.PreferMountedVols = true;
+               if (dcr->VolumeName[0]) {
+                  volume_unused(dcr);
+               }
+               goto bail_out;
+            }
+            if (dcr->dev->num_writers != 0) {
+               if (dcr->VolumeName[0]) {
+                  volume_unused(dcr);
+               }
                goto bail_out;
             }
          }
@@ -1145,7 +1162,7 @@ static int reserve_device(RCTX &rctx)
       pm_strcpy(dev_name, rctx.device->hdr.name);
       bash_spaces(dev_name);
       ok = dir->fsend(OK_device, dev_name.c_str());  /* Return real device name */
-      Dmsg2(dbglvl, "jid=%u >dird changer: %s", jid(), dir->msg);
+      Dmsg2(dbglvl, "jid=%u >dird: %s", jid(), dir->msg);
    } else {
       ok = true;
    }
@@ -1270,6 +1287,52 @@ bail_out:
    return ok;
 }
 
+static int is_pool_ok(DCR *dcr)
+{
+   DEVICE *dev = dcr->dev;
+   JCR *jcr = dcr->jcr;
+
+   /* Now check if we want the same Pool and pool type */
+   if (strcmp(dev->pool_name, dcr->pool_name) == 0 &&
+       strcmp(dev->pool_type, dcr->pool_type) == 0) {
+      /* OK, compatible device */
+      Dmsg2(dbglvl, "jid=%u OK dev: %s num_writers=0, reserved, pool matches\n",
+         jcr->JobId, dev->print_name());
+      return 1;
+   } else {
+      /* Drive Pool not suitable for us */
+      Mmsg(jcr->errmsg, _(
+"3608 JobId=%u wants Pool=\"%s\" but have Pool=\"%s\" nreserve=%d on drive %s.\n"), 
+            jcr->JobId, dcr->pool_name, dev->pool_name,
+            dev->reserved_device, dev->print_name());
+      queue_reserve_message(jcr);
+      Dmsg3(dbglvl, "jid=%u failed: busy num_writers=0, reserved, pool=%s wanted=%s\n",
+         (int)jcr->JobId, dev->pool_name, dcr->pool_name);
+   }
+   return 0;
+}
+
+static bool is_max_jobs_ok(DCR *dcr) 
+{
+   DEVICE *dev = dcr->dev;
+   JCR *jcr = dcr->jcr;
+
+   Dmsg5(dbglvl, "jid=%u MaxJobs=%d Jobs=%d reserves=%d Vol=%s\n",
+         (uint32_t)jcr->JobId, dcr->VolCatInfo.VolCatMaxJobs,
+         dcr->VolCatInfo.VolCatJobs, dev->reserved_device,
+         dcr->VolumeName);
+   if (dcr->VolCatInfo.VolCatMaxJobs > 0 && dcr->VolCatInfo.VolCatMaxJobs <=
+        (dcr->VolCatInfo.VolCatJobs + dev->reserved_device)) {
+      /* Max Job Vols depassed or already reserved */
+      Mmsg(jcr->errmsg, _("3610 JobId=%u Volume max jobs exceeded on drive %s.\n"), 
+            (uint32_t)jcr->JobId, dev->print_name());
+      queue_reserve_message(jcr);
+      Dmsg2(dbglvl, "jid=%u reserve dev failed: %s", (uint32_t)jcr->JobId, jcr->errmsg);
+      return false;                /* wait */
+   }
+   return true;
+}
+
 /*
  * Returns: 1 if drive can be reserved
  *          0 if we should wait
@@ -1374,32 +1437,13 @@ static int can_reserve_drive(DCR *dcr, RCTX &rctx)
    if (dev->num_writers == 0) {
       /* Now check if there are any reservations on the drive */
       if (dev->reserved_device) {           
-         /* Now check if we want the same Pool and pool type */
-         if (strcmp(dev->pool_name, dcr->pool_name) == 0 &&
-             strcmp(dev->pool_type, dcr->pool_type) == 0) {
-            /* OK, compatible device */
-            Dmsg2(dbglvl, "jid=%u OK dev: %s num_writers=0, reserved, pool matches\n",
-               jcr->JobId, dev->print_name());
-            return 1;
-         } else {
-            /* Drive Pool not suitable for us */
-            Mmsg(jcr->errmsg, _(
-"3608 JobId=%u wants Pool=\"%s\" but have Pool=\"%s\" nreserve=%d on drive %s.\n"), 
-                  jcr->JobId, dcr->pool_name, dev->pool_name,
-                  dev->reserved_device, dev->print_name());
-            queue_reserve_message(jcr);
-            Dmsg3(dbglvl, "jid=%u failed: busy num_writers=0, reserved, pool=%s wanted=%s\n",
-               (int)jcr->JobId, dev->pool_name, dcr->pool_name);
-            return 0;                 /* wait */
+         if (!is_max_jobs_ok(dcr)) {
+            return 0;
          }
+         return is_pool_ok(dcr);
       } else if (dev->can_append()) {
-         /* Device in append mode, check if changing pool */
-         if (strcmp(dev->pool_name, dcr->pool_name) == 0 &&
-             strcmp(dev->pool_type, dcr->pool_type) == 0) {
-            Dmsg2(dbglvl, "jid=%u OK dev: %s num_writers=0, can_append, pool matches.\n",
-               jcr->JobId, dev->print_name());
-            /* OK, compatible device */
-            return 1;
+         if (is_pool_ok(dcr)) {
+            return 1; 
          } else {
             /* Changing pool, unload old tape if any in drive */
             Dmsg1(dbglvl, "jid=%u OK dev: num_writers=0, not reserved, pool change, unload changer\n",
@@ -1419,22 +1463,10 @@ static int can_reserve_drive(DCR *dcr, RCTX &rctx)
     *  available if pool is the same).
     */
    if (dev->can_append() || dev->num_writers > 0) {
-      /* Yes, now check if we want the same Pool and pool type */
-      if (strcmp(dev->pool_name, dcr->pool_name) == 0 &&
-          strcmp(dev->pool_type, dcr->pool_type) == 0) {
-         Dmsg2(dbglvl, "jid=%u OK dev: %s num_writers>=0, can_append, pool matches.\n",
-            jcr->JobId, dev->print_name());
-         /* OK, compatible device */
-         return 1;
-      } else {
-         /* Drive Pool not suitable for us */
-         Mmsg(jcr->errmsg, _("3609 JobId=%u wants Pool=\"%s\" but has Pool=\"%s\" on drive %s.\n"), 
-               jcr->JobId, dcr->pool_name, dev->pool_name, dev->print_name());
-         queue_reserve_message(jcr);
-         Dmsg3(dbglvl, "jid=%u failed: busy num_writers>0, can_append, pool=%s wanted=%s\n",
-            (int)jcr->JobId, dev->pool_name, dcr->pool_name);
-         return 0;                    /* wait */
+      if (!is_max_jobs_ok(dcr)) {
+         return 0;
       }
+      return is_pool_ok(dcr);
    } else {
       Pmsg1(000, _("Logic error!!!! JobId=%u Should not get here.\n"), (int)jcr->JobId);
       Mmsg(jcr->errmsg, _("3910 JobId=%u Logic error!!!! drive %s Should not get here.\n"),
diff --git a/bacula/src/version.h b/bacula/src/version.h
index 55e6c1b621..eb19750a59 100644
--- a/bacula/src/version.h
+++ b/bacula/src/version.h
@@ -3,9 +3,9 @@
  */
 
 #undef  VERSION
-#define VERSION "2.3.4"
-#define BDATE   "14 September 2007"
-#define LSMDATE "14Sep07"
+#define VERSION "2.3.5"
+#define BDATE   "23 September 2007"
+#define LSMDATE "23Sep07"
 
 #define PROG_COPYRIGHT "Copyright (C) %d-2007 Free Software Foundation Europe e.V.\n"
 #define BYEAR "2007"       /* year for copyright messages in progs */
diff --git a/bacula/technotes-2.3 b/bacula/technotes-2.3
index af73dc2112..69ce06e069 100644
--- a/bacula/technotes-2.3
+++ b/bacula/technotes-2.3
@@ -1,6 +1,14 @@
               Technical notes on version 2.3
 
 General:
+23Sep07 
+kes  Rework the reservation system to take into account that the Director
+     might give us a Volume that is different from the current one being
+     used, and to ensure that we don't exceed Maximum Volume Jobs.
+     This fixes (mostly) bug #947 '  Maximum Volume Jobs = 1 produces 
+     fatal error with multiple jobs running'
+kes  Add more debug code in reservation system.
+kes  Implement maxvol-test to check bug #947.
 22Sep07 
 kes  Add code to handle tray monitor separated from Win32 FD.
 kes  Fix display of Win32 tray monitor after reboot. Fixes bug #952.