X-Git-Url: http://git.pippins.net/embedvideo/.git/?a=blobdiff_plain;f=zfs-replicate;h=09cb3babb7600f0526a14b4b2c2f945f41660ea4;hb=984d48e66a916fd9ba533ae19b43aafd449dad77;hp=7c6e65027f64f40f6af4bc56860bda74a688bfc1;hpb=80e5913b92d256486d08d966ab2fa34d2d6046fb;p=zfs-ubuntu%2F.git

diff --git a/zfs-replicate b/zfs-replicate
index 7c6e650..09cb3ba 100755
--- a/zfs-replicate
+++ b/zfs-replicate
@@ -1,46 +1,232 @@
 #/bin/bash
 
-set -x
-
 # Usage: replicate <hostname> <zfs filesystem>
 remote=$1
 remote_fs=$2
+remote_pool=${2%%/*}
+remote_lockdir="/tmp/zfs-admin-lock"
 
-# change to match the name of the local backup pool
+# Set the name of the local pool used to store the backup of the remote
 local_pool=backups
 
+# Set the email address to send notification to
+mailto=root@pippins.net
+
+# When this variable is set, local filesystems will be destroyed 
+# before receiving a full streams into them from the remote source.
+destroy_local_filesystem_on_full_replicate=0
+
 # The ssh connection doesn't find zfs without this.
 zfs=/usr/sbin/zfs
 
+# Setup our cleanup and exit trap
+cleanup() {
+  ssh $remote rm -rf "$remote_lockdir"
+  exit
+}
+trap cleanup INT
+trap cleanup EXIT
+
+# Make sure we have valid arguments
+if [[ -z "$remote" ]] || [[ -z "$remote_fs" ]]; then
+  echo "Usage: $0 <hostname> <zfs filesystem>"
+  exit 1
+fi
+
+# Make sure the local pool and local receiving filesystem exist, or print some errors
+zpool list -H "$local_pool" >/dev/null 2>&1
+if [ $? != 0 ]; then
+  echo >&2 "-E- The local pool, '$local_pool' doesn't seem to exist."
+  exit 1
+fi
+zfs list "$local_pool/$remote_pool" >/dev/null 2>&1
+if [ $? != 0 ]; then
+  echo >&2 "-I- The local filesystem for the remote pool, '$local_pool/$remote_pool' doesn't seem to exist."
+  echo >&2 "    Creating the local filesystem to receive the remote pool into: $local_pool/$remote_pool"
+  $zfs create $local_pool/$remote_pool
+  if [ $? != 0 ]; then
+    echo "-E- remote $zfs create command failed"
+    exit 1
+  fi
+fi
+
+# Obtain the zpool guid for the local pool
+local_pool_guid=`zpool get guid $local_pool 2>&1 | grep $local_pool | awk '{ print $3 }'`
+zpool get guid $local_pool > /dev/null 2>&1
+if [ $? != 0 ]; then
+  echo >&2 "-E- Unable to extract the guid for the local pool: $local_pool"
+  exit 1
+fi
+
+# Turn on shell verbosity
+set -x
+
+# Create the remote lockdir before continuing with the replicate
+# Spinlock on creating the lock
+maxsleeptime=60
+maxattempts=100
+attempts=0
+while true; do
+  ssh $remote mkdir "$remote_lockdir" >/dev/null 2>&1
+  if [ $? != 0 ]; then
+    # Another zfs admin tool is running.
+    # Wait a random amount of time and try again
+    ransleep=$(($RANDOM % $maxsleeptime))
+    sleep $ransleep
+    ((attempts=attempts+1))
+  else 
+    # No other zfs admin tool is running, we can now.
+    break
+  fi
+  if [[ $attempts -gt $maxattempts ]]; then
+    # We've exceeded our maximum while loop count
+    echo "-W- The zfs filesystem has been locked down. Skipping replicate operation."
+    ssh $remote ls -ld $remote_lockdir | /usr/bin/mailx -s "zfs-replicate-all unable to obtain zfs admin lock" $mailto
+    exit 1
+  fi
+done
+
+# Setup our backup marker names
+current_backup_marker=${remote_fs}@current-backup-${local_pool_guid}
+previous_backup_marker=${remote_fs}@previous-backup-${local_pool_guid}
+
 # List the snapshots on the remote machine.
 remote_list=$(mktemp /tmp/replicate.XXXXXX)
 ssh $remote \
     $zfs list -H -t snapshot |
     grep ^${remote_fs}@ |
     awk '{print$1}' > $remote_list
+if [ $? != 0 ]; then
+  echo "-E- remote $zfs list command failed"
+  exit 1
+fi
 
 # List the snapshots on the local machine.
+# Don't list the current backup marker if it exists on the local side.
+# If you do, it can mess up the common finding algorithm below.
 local_list=$(mktemp /tmp/replicate.XXXXXX)
 $zfs list -H -t snapshot |
     grep ^${local_pool}/${remote_fs}@ |
-    awk '{gsub(/^${local_pool}./,"",$1); print$1}' > $local_list
+    grep -v ^${local_pool}/${current_backup_marker} | 
+    awk "{gsub(/^$local_pool./,\"\",\$1); print\$1}" > $local_list
+if [ $? != 0 ]; then
+  echo "-E- local $zfs list command failed"
+  exit 1
+fi
+
+# Destroy the current backup marker snapshot on the remote system if it exists
+grep -q ${current_backup_marker} $remote_list
+if [ $? == 0 ]; then
+  ssh $remote $zfs destroy ${current_backup_marker} 
+  if [ $? != 0 ]; then
+    echo "-E- remote $zfs destroy command failed"
+    exit 1
+  fi
+fi
+
+# Create the current backup marker snapshot on the remote system
+ssh $remote $zfs snapshot ${current_backup_marker}
+if [ $? != 0 ]; then
+  echo "-E- remote $zfs snapshot command failed"
+  exit 1
+fi
 
-# See what the most recent snapshot on the remote end is.
-latest=$(tail -n 1 $remote_list)
+# Check to see if the previous backup marker exists in the remote snapshot list.
+# Check to see if the previous backup marker exists in the local snapshot list.
+# If the previous backup markers exists, perform an incremental replicate. Else:
+# 1) check to see if a common snapshot exists, and perform an incremental replicate.
+# 2) if no common snapshot exists, destroy the local filesystem, and perform a full replicate.
+grep -q ${previous_backup_marker} $remote_list
+no_markers=$?
+grep -q ${previous_backup_marker} $local_list
+no_markers=$(($no_markers || $?))
 
-# I did this to make sure that diff would always display the most recent common
-echo bogus.remote >> $remote_list
-echo bogus.local  >> $local_list
-common=$(diff -u $remote_list $local_list | grep '^ ' | tail -n 1)
+if [ $no_markers == 0 ]; then
+  # We found backup markers, incrementally send the new snaps
 
-if [ -n "$common" ]; then 
-  # We found a common snapshot
-  ssh $remote $zfs send -R -I${common/*@/@} $latest |
-      $zfs receive -vF -d ${local_pool}/${remote_fs%/*}
+  # First, rollback the local pool to the previous backup marker in case the previous
+  # backup was interrupted for some reason. If we don't do this, the zfs send -R command
+  # below may complain about snaps already existing as it tries to resend from the 
+  # previous backup marker again from a previously interrupted replicate.
+  $zfs rollback -r ${local_pool}/${previous_backup_marker} 
+  if [ $? != 0 ]; then
+    echo "-E- remote incremental $zfs rollback command failed"
+    exit 1
+  fi
+  # Now it should be safe to send the snaps
+  ssh $remote $zfs send -R -I${previous_backup_marker} ${current_backup_marker} | 
+      $zfs receive -vF -d ${local_pool}/${remote_pool}
+  if [ $? != 0 ]; then
+    echo "-E- remote incremental $zfs send command failed"
+    exit 1
+  fi
 else
-  # We did not find a common snapshot, so send the entire filesystem
-  ssh $remote $zfs send -R $latest |
-      $zfs receive -vF -d ${local_pool}/${remote_fs%/*}
-endif
+  # We didn't find any backup markers, next check to see if we have a common snapshot.
 
+  # See what the most recent snapshot on the remote end is.
+  latest=$(tail -n 1 $remote_list)
+
+  # I did this to make sure that diff would always display the most recent common
+  # Since we're keying off the context of the diff, we need to ensure we will get context
+  # by injecting a known difference in case no others exist in the lists.
+  echo bogus.remote >> $remote_list
+  echo bogus.local  >> $local_list
+  common=$(diff -u $remote_list $local_list | grep '^ ' | tail -n 1)
+
+  if [[ -n "$common" ]]; then
+    # We found a common snapshot, incrementally send the new snaps
+    ssh $remote $zfs send -R -I${common/*@/@} ${current_backup_marker} |
+        $zfs receive -vF -d ${local_pool}/${remote_pool}
+    if [ $? != 0 ]; then
+      echo "-E- remote incremental $zfs send command failed"
+      exit 1
+    fi
+  else
+    # We did not find any markers or a common snapshot
+    # At this point, we'll have to send the entire filesystem
+    # Destroy the local filesystem if it exists before receving the full replicate
+    zfs list ${local_pool}/${remote_fs} > /dev/null 2>&1
+    if [ $? == 0 ]; then
+      if [[ $destroy_local_filesystem_on_full_replicate == 1 ]]; then
+        $zfs destroy -r ${local_pool}/${remote_fs}
+        if [ $? != 0 ]; then
+          echo "-E- remote full $zfs destroy command failed"
+          exit 1
+        fi
+      else
+        echo "-W- We need to destroy a local filesystem before receiving a full stream."
+	echo "    However, since the option is set to prevent this, skipping replicate operation."
+        echo "$zfs destroy -r ${local_pool}/${remote_fs} not able to run" | /usr/bin/mailx -s "zfs-replicate-all unable to destroy local filesystem" $mailto
+        exit 1
+      fi
+    fi
+    # Send the full filesystem
+    ssh $remote $zfs send -R ${current_backup_marker} |
+        $zfs receive -vF -d ${local_pool}/${remote_pool}
+    if [ $? != 0 ]; then
+      echo "-E- remote full $zfs send command failed"
+      exit 1
+    fi
+  fi
+fi
+ 
+# destroy the previous backup markers now that we've replicated past them
+# don't check the return codes here because these may not exist, and that is ok
+$zfs destroy ${local_pool}/${previous_backup_marker} > /dev/null 2>&1
+ssh $remote $zfs destroy ${previous_backup_marker} > /dev/null 2>&1
+
+# Rename the current backup marker to be the previous backup marker
+$zfs rename ${local_pool}/${current_backup_marker} ${local_pool}/${previous_backup_marker}
+if [ $? != 0 ]; then
+  echo "-E- local $zfs rename command failed"
+  exit 1
+fi
+ssh $remote $zfs rename ${current_backup_marker} ${previous_backup_marker}
+if [ $? != 0 ]; then
+  echo "-E- remote $zfs rename command failed"
+  exit 1
+fi
+   
+# Remove tmp files
 rm -f $local_list $remote_list
+