Merge pull request #1898 from phillxnet/1894_inconsistent_balance_beh…

…aviour_on_single_raid_pool

inconsistent balance behaviour on single raid pool. Fixes #1894

src/rockstor/fs/btrfs.py

@@ -138,7 +138,7 @@ def pool_raid(mnt_pt):
         if (len(fields) > 1):
             block = fields[0][:-1].lower()
             raid = fields[1][:-1].lower()
-            if block not in raid_d and raid is not 'DUP':
+            if block not in raid_d:
                 raid_d[block] = raid
     if (raid_d['metadata'] == 'single'):
         raid_d['data'] = raid_d['metadata']
@@ -1225,22 +1225,23 @@ def scrub_status(pool):
 @task()
 def start_balance(mnt_pt, force=False, convert=None):
     cmd = ['btrfs', 'balance', 'start', mnt_pt]
-    # TODO: Confirm -f is doing what is intended, man states for reducing
-    # TODO: metadata from say raid1 to single.
     # With no filters we also get a warning that block some balances due to
     # expected long execution time, in this case "--full-balance" is required.
-    # N.B. currently force in Web-UI does not mean force here.
-    if (force):
+    if force:
         cmd.insert(3, '-f')
-    if (convert is not None):
+    if convert is not None:
         cmd.insert(3, '-dconvert=%s' % convert)
+        # Override metadata on single pools to be dup, as per btrfs default.
+        if convert == 'single':
+            convert = 'dup'
         cmd.insert(3, '-mconvert=%s' % convert)
     else:
         # As we are running with no convert filters a warning and 10 second
         # countdown with ^C prompt will result unless we use "--full-balance".
         # This warning is now present in the Web-UI "Start a new balance"
         # button tooltip.
         cmd.insert(3, '--full-balance')
+    logger.debug('Balance command ({}).'.format(cmd))
     run_command(cmd)
 
 

src/rockstor/storageadmin/static/storageadmin/js/views/add_pool.js

@@ -191,7 +191,7 @@ AddPoolView = Backbone.View.extend({
         this.$('#raid_level').tooltip({
             html: true,
             placement: 'right',
-            title: 'Desired RAID level of the pool<br><strong>Single</strong>: No software raid. (Recommended while using hardware raid).<br><strong>Raid0</strong>, <strong>Raid1</strong>, <strong>Raid10</strong>, <strong>Raid5</strong>, and <strong>Raid6</strong> are similar to conventional raid levels. See documentation for more information.<br><strong>WARNING: Raid5 and Raid6 are not production-ready</strong>'
+            title: 'Software RAID level<br><strong>Single</strong>: No RAID - one or more devices (-m dup enforced).<br><strong>Raid0</strong>, <strong>Raid1</strong>, <strong>Raid10</strong>, and the parity based <strong>Raid5</strong> & <strong>Raid6</strong> levels are all similar to conventional raid but chunk based, not device based. See docs for more info.<br><strong>WARNING: Raid5 and Raid6 are not production-ready</strong>'
         });
 
         this.$('#compression').tooltip({

src/rockstor/storageadmin/static/storageadmin/js/views/pool/resize/add_disks.js

@@ -143,7 +143,7 @@ PoolAddDisks = RockstorWizardPage.extend({
         Handlebars.registerHelper('display_raid_levels', function(){
             var html = '';
             var _this = this;
-            var levels = ['raid0', 'raid1', 'raid10', 'raid5', 'raid6'];
+            var levels = ['single', 'raid0', 'raid1', 'raid10', 'raid5', 'raid6'];
             _.each(levels, function(level) {
                 if (_this.raidLevel != level) {
                     html += '<option value="' + level + '">' + level + '</option>';

src/rockstor/storageadmin/static/storageadmin/js/views/pool/resize/raid_change.js

@@ -77,7 +77,7 @@ PoolRaidChange = RockstorWizardPage.extend({
         Handlebars.registerHelper('display_raid_levels', function() {
             var html = '';
             var _this = this;
-            var levels = ['raid0', 'raid1', 'raid10', 'raid5', 'raid6'];
+            var levels = ['single', 'raid0', 'raid1', 'raid10', 'raid5', 'raid6'];
             _.each(levels, function(level) {
                 if (_this.raidLevel != level) {
                     html += '<option value="' + level + '">' + level + '</option>';

src/rockstor/storageadmin/static/storageadmin/js/views/pool_details_layout_view.js

@@ -113,7 +113,12 @@ PoolDetailsLayoutView = RockstorLayoutView.extend({
         this.$('#ph-pool-usage').html(this.subviews['pool-usage'].render().el);
         this.$('#ph-pool-scrubs').html(this.subviews['pool-scrubs'].render().el);
         this.$('#ph-pool-rebalances').html(this.subviews['pool-rebalances'].render().el);
-        this.renderDataTables();
+        // Sort all SubView tables in descending order by initial column.
+        // This way we see the latest Scrub / Balance items at the top.
+        var customs = {
+            'order': [[0, 'desc']]
+        };
+        this.renderDataTables(customs);
 
 
         this.$('#ph-compression-info').html(this.compression_info_template({

src/rockstor/storageadmin/views/pool.py

@@ -212,6 +212,13 @@ def _remount(cls, request, pool):
 
     def _balance_start(self, pool, force=False, convert=None):
         mnt_pt = mount_root(pool)
+        if convert is None and pool.raid == 'single':
+            # Btrfs balance without convert filters will convert dup level
+            # metadata on a single level data pool to raid1 on multi disk
+            # pools. Avoid by explicit convert in this instance.
+            logger.info('Preserve single data, dup metadata by explicit '
+                        'convert.')
+            convert = 'single'
         start_balance.async(mnt_pt, force=force, convert=convert)
         tid = 0
         count = 0
@@ -375,7 +382,9 @@ def put(self, request, pid, command):
                                  'web-ui' % d.name)
                         handle_exception(Exception(e_msg), request)
 
-                if (pool.raid != 'single' and new_raid == 'single'):
+                if pool.raid == 'single' and new_raid == 'raid10':
+                    # TODO: Consider removing once we have better space calc.
+                    # Avoid extreme raid level change upwards (space issues).
                     e_msg = ('Pool migration from %s to %s is not supported.'
                              % (pool.raid, new_raid))
                     handle_exception(Exception(e_msg), request)
@@ -404,7 +413,12 @@ def put(self, request, pid, command):
                     handle_exception(Exception(e_msg), request)
 
                 resize_pool(pool, dnames)
-                tid = self._balance_start(pool, convert=new_raid)
+                # During dev add we also offer raid level change, if selected
+                # blanket apply '-f' to allow for reducing metadata integrity.
+                force = False
+                if new_raid != pool.raid:
+                    force = True
+                tid = self._balance_start(pool, force=force, convert=new_raid)
                 ps = PoolBalance(pool=pool, tid=tid)
                 ps.save()