[lvm-devel] master - activation: Add "degraded" activation mode
Jonathan Brassow
jbrassow at fedoraproject.org
Thu Jul 10 03:58:12 UTC 2014
Gitweb: http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=be75076dfc842945a03fa42073e9e03f51bd3a3c
Commit: be75076dfc842945a03fa42073e9e03f51bd3a3c
Parent: a098cba0ebbd0682570cff2fc756a59533321f03
Author: Jonathan Brassow <jbrassow at redhat.com>
AuthorDate: Wed Jul 9 22:56:11 2014 -0500
Committer: Jonathan Brassow <jbrassow at redhat.com>
CommitterDate: Wed Jul 9 22:56:11 2014 -0500
activation: Add "degraded" activation mode
Currently, we have two modes of activation, an unnamed nominal mode
(which I will refer to as "complete") and "partial" mode. The
"complete" mode requires that a volume group be 'complete' - that
is, no missing PVs. If there are any missing PVs, no affected LVs
are allowed to activate - even RAID LVs which might be able to
tolerate a failure. The "partial" mode allows anything to be
activated (or at least attempted). If a non-redundant LV is
missing a portion of its addressable space due to a device failure,
it will be replaced with an error target. RAID LVs will either
activate or fail to activate depending on how badly their
redundancy is compromised.
This patch adds a third option, "degraded" mode. This mode can
be selected via the '--activationmode {complete|degraded|partial}'
option to lvchange/vgchange. It can also be set in lvm.conf.
The "degraded" activation mode allows RAID LVs with a sufficient
level of redundancy to activate (e.g. a RAID5 LV with one device
failure, a RAID6 with two device failures, or RAID1 with n-1
failures). RAID LVs with too many device failures are not allowed
to activate - nor are any non-redundant LVs that may have been
affected. This patch also makes the "degraded" mode the default
activation mode.
The degraded activation mode does not yet work in a cluster. A
new cluster lock flag (LCK_DEGRADED_MODE) will need to be created
to make that work. Currently, there is limited space for this
extra flag and I am looking for possible solutions. One possible
solution is to usurp LCK_CONVERT, as it is not used. When the
locking_type is 3, the degraded mode flag simply gets dropped and
the old ("complete") behavior is exhibited.
---
WHATS_NEW | 1 +
conf/example.conf.in | 25 +++++++++
lib/activate/activate.c | 120 ++++++++++++++++++++++++++++++++++++++++-
lib/activate/dev_manager.c | 9 ++-
lib/commands/toolcontext.h | 1 +
lib/config/config_settings.h | 1 +
lib/config/defaults.h | 1 +
man/lvchange.8.in | 19 +++++++
man/vgchange.8.in | 18 ++++++
tools/args.h | 2 +
tools/commands.h | 8 ++-
tools/lvmcmdline.c | 28 +++++++++-
tools/toollib.c | 3 +-
13 files changed, 226 insertions(+), 10 deletions(-)
diff --git a/WHATS_NEW b/WHATS_NEW
index 21668f2..29a0aa3 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -1,5 +1,6 @@
Version 2.02.108 -
=================================
+ Add "degraded" activation mode and make it the default.
Add separate lv_active_{locally,remotely,exclusively} LV reporting fields.
Recognize "auto"/"unmanaged" values in selection for appropriate fields only.
Add report/binary_values_as_numeric lvm.conf option for binary values as 0/1.
diff --git a/conf/example.conf.in b/conf/example.conf.in
index e1afbb6..11f50f0 100644
--- a/conf/example.conf.in
+++ b/conf/example.conf.in
@@ -1011,6 +1011,31 @@ activation {
# are no progress reports, but the process is awoken immediately the
# operation is complete.
polling_interval = 15
+
+ # 'activation_mode' determines how logical volumes are activated if
+ # devices are missing. Possible settings are:
+ #
+ # "complete" - Only allow activation of an LV if all of the PVs
+ # that it uses are available (i.e. the volume group
+ # is complete). There may be a failed PV in the
+ # volume group; but if a particular LV is not on that
+ # PV, it is still allowed to activate in this mode.
+ #
+ # "degraded" - Like "complete", except that RAID logical volumes of
+ # segment type "raid{1,4,5,6,10}" are activated if
+ # they have sufficient redundancy to present the entire
+ # addressable range of the logical volume.
+ #
+ # "partial" - Allow activation for any logical volume - even if
+ # a missing or failed PV would cause a portion of the
+ # logical volume to be inaccessible. (E.g. a stripe
+ # volume that has lost one of its members would be
+ # unable to access a portion of the logical volume.)
+ # This setting is not recommended for normal use.
+ #
+ # This setting was introduced in LVM version 2.02.108. It corresponds
+ # with the '--activationmode' option for lvchange and vgchange.
+ activation_mode = "degraded"
}
# Report settings.
diff --git a/lib/activate/activate.c b/lib/activate/activate.c
index adaff52..70777fd 100644
--- a/lib/activate/activate.c
+++ b/lib/activate/activate.c
@@ -2203,6 +2203,111 @@ out:
return r;
}
+static int _lv_raid_is_redundant(struct logical_volume *lv)
+{
+ struct lv_segment *raid_seg = first_seg(lv);
+ uint32_t copies;
+ uint32_t i, s, rebuilds_per_group = 0;
+ uint32_t failed_components = 0;
+
+ if (!(lv->status & PARTIAL_LV)) {
+ /*
+ * Redundant, but this function shouldn't
+ * be called in this case.
+ */
+ log_error(INTERNAL_ERROR "%s is not a partial LV", lv->name);
+ return 1;
+ }
+
+ if (!lv_is_raid(lv))
+ return 0; /* Not RAID, not redundant */
+
+ if (!strcmp(raid_seg->segtype->name, "raid10")) {
+ /* FIXME: We only support 2-way mirrors in RAID10 currently */
+ copies = 2;
+ for (i = 0; i < raid_seg->area_count * copies; i++) {
+ s = i % raid_seg->area_count;
+ if (!(i % copies))
+ rebuilds_per_group = 0;
+ if ((seg_lv(raid_seg, s)->status & PARTIAL_LV) ||
+ (seg_metalv(raid_seg, s)->status & PARTIAL_LV) ||
+ lv_is_virtual(seg_lv(raid_seg, s)) ||
+ lv_is_virtual(seg_metalv(raid_seg, s)))
+ rebuilds_per_group++;
+ if (rebuilds_per_group >= copies) {
+ log_debug("An entire mirror group "
+ "has failed in %s", lv->name);
+ return 0; /* Not redundant */
+ }
+ }
+ return 1; /* Redundant */
+ }
+
+ for (s = 0; s < raid_seg->area_count; s++) {
+ if ((seg_lv(raid_seg, s)->status & PARTIAL_LV) ||
+ (seg_metalv(raid_seg, s)->status & PARTIAL_LV) ||
+ lv_is_virtual(seg_lv(raid_seg, s)) ||
+ lv_is_virtual(seg_metalv(raid_seg, s)))
+ failed_components++;
+ }
+ if (failed_components == raid_seg->area_count) {
+ log_debug("All components in %s have failed", lv->name);
+ return 0;
+ } else if (raid_seg->segtype->parity_devs &&
+ (failed_components > raid_seg->segtype->parity_devs)) {
+ log_debug("More than %u components from (%s) %s/%s have failed",
+ raid_seg->segtype->parity_devs,
+ raid_seg->segtype->ops->name(raid_seg),
+ lv->vg->name, lv->name);
+ return 0;
+ }
+
+ return 1;
+}
+
+static int _lv_is_not_degraded_capable(struct logical_volume *lv, void *data)
+{
+ int *not_capable = (int *)data;
+ uint32_t s;
+ struct lv_segment *seg;
+
+ if (!(lv->status & PARTIAL_LV))
+ return 1;
+
+ if (lv_is_raid(lv))
+ return _lv_raid_is_redundant(lv);
+
+ /* Ignore RAID sub-LVs. */
+ if (lv_is_raid_type(lv))
+ return 1;
+
+ dm_list_iterate_items(seg, &lv->segments)
+ for (s = 0; s < seg->area_count; s++)
+ if (seg_type(seg, s) != AREA_LV) {
+ log_debug("%s is not capable of degraded mode",
+ lv->name);
+ *not_capable = 1;
+ }
+
+ return 1;
+}
+
+static int lv_is_degraded_capable(struct logical_volume *lv)
+{
+ int not_capable = 0;
+
+ if (!(lv->status & PARTIAL_LV))
+ return 1;
+
+ if (!_lv_is_not_degraded_capable(lv, ¬_capable) || not_capable)
+ return 0;
+
+ if (!for_each_sub_lv(lv, _lv_is_not_degraded_capable, ¬_capable))
+ log_error(INTERNAL_ERROR "for_each_sub_lv failure.");
+
+ return !not_capable;
+}
+
static int _lv_activate(struct cmd_context *cmd, const char *lvid_s,
struct lv_activate_opts *laopts, int filter,
struct logical_volume *lv)
@@ -2225,9 +2330,18 @@ static int _lv_activate(struct cmd_context *cmd, const char *lvid_s,
}
if ((!lv->vg->cmd->partial_activation) && (lv->status & PARTIAL_LV)) {
- log_error("Refusing activation of partial LV %s. Use --partial to override.",
- lv->name);
- goto out;
+ if (!lv_is_degraded_capable(lv)) {
+ log_error("Refusing activation of partial LV %s. "
+ "Use '--activationmode partial' to override.",
+ lv->name);
+ goto out;
+ } else if (!lv->vg->cmd->degraded_activation) {
+ log_error("Refusing activation of partial LV %s. "
+ "Try '--activationmode degraded'.",
+ lv->name);
+ goto out;
+ }
+ log_print_unless_silent("Attempting activation of partial RAID LV, %s.", lv->name);
}
if (lv_has_unknown_segments(lv)) {
diff --git a/lib/activate/dev_manager.c b/lib/activate/dev_manager.c
index e30b176..0305bb4 100644
--- a/lib/activate/dev_manager.c
+++ b/lib/activate/dev_manager.c
@@ -2067,9 +2067,12 @@ int add_areas_line(struct dev_manager *dm, struct lv_segment *seg,
stat(name, &info) < 0 || !S_ISBLK(info.st_mode))) ||
(seg_type(seg, s) == AREA_LV && !seg_lv(seg, s))) {
if (!seg->lv->vg->cmd->partial_activation) {
- log_error("Aborting. LV %s is now incomplete "
- "and --partial was not specified.", seg->lv->name);
- return 0;
+ if (!seg->lv->vg->cmd->degraded_activation ||
+ !lv_is_raid_type(seg->lv)) {
+ log_error("Aborting. LV %s is now incomplete "
+ "and '--activationmode partial' was not specified.", seg->lv->name);
+ return 0;
+ }
}
if (!_add_error_area(dm, node, seg, s))
return_0;
diff --git a/lib/commands/toolcontext.h b/lib/commands/toolcontext.h
index 162af55..d06dd7d 100644
--- a/lib/commands/toolcontext.h
+++ b/lib/commands/toolcontext.h
@@ -86,6 +86,7 @@ struct cmd_context {
unsigned handles_unknown_segments:1;
unsigned use_linear_target:1;
unsigned partial_activation:1;
+ unsigned degraded_activation:1;
unsigned auto_set_activation_skip:1;
unsigned si_unit_consistency:1;
unsigned report_binary_values_as_numeric:1;
diff --git a/lib/config/config_settings.h b/lib/config/config_settings.h
index 2ddf888..7289a04 100644
--- a/lib/config/config_settings.h
+++ b/lib/config/config_settings.h
@@ -212,6 +212,7 @@ cfg(activation_use_mlockall_CFG, "use_mlockall", activation_CFG_SECTION, 0, CFG_
cfg(activation_monitoring_CFG, "monitoring", activation_CFG_SECTION, 0, CFG_TYPE_BOOL, DEFAULT_DMEVENTD_MONITOR, vsn(2, 2, 63), NULL)
cfg(activation_polling_interval_CFG, "polling_interval", activation_CFG_SECTION, 0, CFG_TYPE_INT, DEFAULT_INTERVAL, vsn(2, 2, 63), NULL)
cfg(activation_auto_set_activation_skip_CFG, "auto_set_activation_skip", activation_CFG_SECTION, 0, CFG_TYPE_BOOL, DEFAULT_AUTO_SET_ACTIVATION_SKIP, vsn(2,2,99), NULL)
+cfg(activation_mode_CFG, "activation_mode", activation_CFG_SECTION, 0, CFG_TYPE_STRING, DEFAULT_ACTIVATION_MODE, vsn(2,2,108), NULL)
cfg(metadata_pvmetadatacopies_CFG, "pvmetadatacopies", metadata_CFG_SECTION, CFG_ADVANCED, CFG_TYPE_INT, DEFAULT_PVMETADATACOPIES, vsn(1, 0, 0), NULL)
cfg(metadata_vgmetadatacopies_CFG, "vgmetadatacopies", metadata_CFG_SECTION, CFG_ADVANCED, CFG_TYPE_INT, DEFAULT_VGMETADATACOPIES, vsn(2, 2, 69), NULL)
diff --git a/lib/config/defaults.h b/lib/config/defaults.h
index 4200dc8..086f7fd 100644
--- a/lib/config/defaults.h
+++ b/lib/config/defaults.h
@@ -163,6 +163,7 @@
#define DEFAULT_PROCESS_PRIORITY -18
#define DEFAULT_AUTO_SET_ACTIVATION_SKIP 1
+#define DEFAULT_ACTIVATION_MODE "degraded"
#define DEFAULT_USE_LINEAR_TARGET 1
#define DEFAULT_STRIPE_FILLER "error"
#define DEFAULT_RAID_REGION_SIZE 512 /* KB */
diff --git a/man/lvchange.8.in b/man/lvchange.8.in
index f7aee8f..39187f0 100644
--- a/man/lvchange.8.in
+++ b/man/lvchange.8.in
@@ -9,6 +9,8 @@ lvchange \(em change attributes of a logical volume
.RI { y | n }]
.RB [ \-a | \-\-activate
.RI [ a | e | l ]{ y | n }]
+.RB [ \-\-activationmode
+.IR { complete | degraded | partial } ]
.RB [ \-k | \-\-setactivationskip { y | n } ]
.RB [ \-K | \-\-ignoreactivationskip ]
.RB [ \-\-alloc
@@ -18,6 +20,7 @@ lvchange \(em change attributes of a logical volume
.RB [ \-C | \-\-contiguous
.RI { y | n }]
.RB [ \-d | \-\-debug ]
+.RB [ \-\-degraded ]
.RB [ \-\-deltag
.IR Tag ]
.RB [ \-\-detachprofile ]
@@ -97,6 +100,22 @@ To deactivate only on the local node use -aln.
Logical volumes with single-host snapshots are always activated
exclusively because they can only be used on one node at once.
.TP
+.BR \-\-activationmode " {" \fIcomplete | \fIdegraded | \fIpartial }
+The activation mode determines whether logical volumes are allowed to
+activate when there are physical volumes missing (e.g. due to a device
+failure). \fIcomplete is the most restrictive; allowing only those
+logical volumes to be activated that are not affected by the missing
+PVs. \fIdegraded allows RAID logical volumes to be activated even if
+they have PVs missing. (Note that the "mirror" segment type is not
+considered a RAID logical volume. The "raid1" segment type should
+be used instead.) Finally, \fIpartial allows any logical volume to
+be activated even if portions are missing due to a missing or failed
+PV. This last option should only be used when performing recovery or
+repair operations. \fIdegraded is the default mode. To change it, modify
+.B activation_mode
+in
+.BR lvm.conf (5).
+.TP
.BR \-k ", " \-\-setactivationskip " {" \fIy | \fIn }
Controls whether Logical Volumes are persistently flagged to be
skipped during activation. By default, thin snapshot volumes are
diff --git a/man/vgchange.8.in b/man/vgchange.8.in
index 9ea2f65..150b77d 100644
--- a/man/vgchange.8.in
+++ b/man/vgchange.8.in
@@ -12,6 +12,8 @@ vgchange \(em change attributes of a volume group
.RB [ \-a | \-\-activate
.RI [ a | e | l ]
.RI { y | n }]
+.RB [ \-\-activationmode
+.IR { complete | degraded | partial } ]
.RB [ \-K | \-\-ignoreactivationskip ]
.RB [ \-\-monitor
.RI { y | n }]
@@ -98,6 +100,22 @@ on the local node.
Logical volumes with single-host snapshots are always activated
exclusively because they can only be used on one node at once.
.TP
+.BR \-\-activationmode " {" \fIcomplete | \fIdegraded | \fIpartial }
+The activation mode determines whether logical volumes are allowed to
+activate when there are physical volumes missing (e.g. due to a device
+failure). \fIcomplete is the most restrictive; allowing only those
+logical volumes to be activated that are not affected by the missing
+PVs. \fIdegraded allows RAID logical volumes to be activated even if
+they have PVs missing. (Note that the "mirror" segment type is not
+considered a RAID logical volume. The "raid1" segment type should
+be used instead.) Finally, \fIpartial allows any logical volume to
+be activated even if portions are missing due to a missing or failed
+PV. This last option should only be used when performing recovery or
+repair operations. \fIdegraded is the default mode. To change it, modify
+.B activation_mode
+in
+.BR lvm.conf (5).
+.TP
.BR \-K ", " \-\-ignoreactivationskip
Ignore the flag to skip Logical Volumes during activation.
.TP
diff --git a/tools/args.h b/tools/args.h
index d4a8643..9632478 100644
--- a/tools/args.h
+++ b/tools/args.h
@@ -109,6 +109,8 @@ arg(ignoreskippedcluster_ARG, '\0', "ignoreskippedcluster", NULL, 0)
arg(splitsnapshot_ARG, '\0', "splitsnapshot", NULL, 0)
arg(readonly_ARG, '\0', "readonly", NULL, 0)
arg(atomic_ARG, '\0', "atomic", NULL, 0)
+arg(activationmode_ARG, '\0', "activationmode", string_arg, 0)
+
/* Allow some variations */
arg(resizable_ARG, '\0', "resizable", yes_no_arg, 0)
diff --git a/tools/commands.h b/tools/commands.h
index 7d36bc5..5fae835 100644
--- a/tools/commands.h
+++ b/tools/commands.h
@@ -103,6 +103,7 @@ xx(lvchange,
"lvchange\n"
"\t[-A|--autobackup y|n]\n"
"\t[-a|--activate [a|e|l]{y|n}]\n"
+ "\t[--activationmode {complete|degraded|partial}"
"\t[--addtag Tag]\n"
"\t[--alloc AllocationPolicy]\n"
"\t[-C|--contiguous y|n]\n"
@@ -141,7 +142,8 @@ xx(lvchange,
"\t[-Z|--zero {y|n}]\n"
"\tLogicalVolume[Path] [LogicalVolume[Path]...]\n",
- addtag_ARG, alloc_ARG, autobackup_ARG, activate_ARG, available_ARG,
+ activationmode_ARG, addtag_ARG, alloc_ARG, autobackup_ARG, activate_ARG,
+ available_ARG,
contiguous_ARG, deltag_ARG, discards_ARG, detachprofile_ARG, force_ARG,
ignorelockingfailure_ARG, ignoremonitoring_ARG, ignoreactivationskip_ARG,
ignoreskippedcluster_ARG, major_ARG, metadataprofile_ARG, minor_ARG,
@@ -933,6 +935,7 @@ xx(vgchange,
"\t[-v|--verbose] " "\n"
"\t[--version]" "\n"
"\t{-a|--activate [a|e|l]{y|n} |" "\n"
+ "\t[--activationmode {complete|degraded|partial}]" "\n"
"\t -c|--clustered {y|n} |" "\n"
"\t -x|--resizeable {y|n} |" "\n"
"\t -l|--logicalvolume MaxLogicalVolumes |" "\n"
@@ -942,7 +945,8 @@ xx(vgchange,
"\t --deltag Tag}\n"
"\t[VolumeGroupName...]\n",
- addtag_ARG, alloc_ARG, allocation_ARG, autobackup_ARG, activate_ARG,
+ activationmode_ARG, addtag_ARG, alloc_ARG, allocation_ARG, autobackup_ARG,
+ activate_ARG,
available_ARG, clustered_ARG, deltag_ARG, detachprofile_ARG,
ignoreactivationskip_ARG, ignorelockingfailure_ARG, ignoremonitoring_ARG,
ignoreskippedcluster_ARG, logicalvolume_ARG, maxphysicalvolumes_ARG,
diff --git a/tools/lvmcmdline.c b/tools/lvmcmdline.c
index 780e9d0..fc51c4a 100644
--- a/tools/lvmcmdline.c
+++ b/tools/lvmcmdline.c
@@ -866,6 +866,8 @@ int version(struct cmd_context *cmd __attribute__((unused)),
static int _get_settings(struct cmd_context *cmd)
{
+ const char *activation_mode;
+
cmd->current_settings = cmd->default_settings;
if (arg_count(cmd, debug_ARG))
@@ -903,10 +905,34 @@ static int _get_settings(struct cmd_context *cmd)
}
cmd->partial_activation = 0;
+ cmd->degraded_activation = 0;
+ activation_mode = find_config_tree_str(cmd, activation_mode_CFG, NULL);
+ if (!activation_mode)
+ activation_mode = DEFAULT_ACTIVATION_MODE;
+
+ if (arg_count(cmd, activationmode_ARG)) {
+ activation_mode = arg_str_value(cmd, activationmode_ARG,
+ activation_mode);
+
+ /* complain only if the two arguments conflict */
+ if (arg_count(cmd, partial_ARG) &&
+ strcmp(activation_mode, "partial")) {
+ log_error("--partial and --activationmode are mutually"
+ " exclusive arguments");
+ return EINVALID_CMD_LINE;
+ }
+ } else if (arg_count(cmd, partial_ARG))
+ activation_mode = "partial";
- if (arg_count(cmd, partial_ARG)) {
+ if (!strcmp(activation_mode, "partial")) {
cmd->partial_activation = 1;
log_warn("PARTIAL MODE. Incomplete logical volumes will be processed.");
+ } else if (!strcmp(activation_mode, "degraded")) {
+ cmd->degraded_activation = 1;
+ log_debug("DEGRADED MODE. Incomplete RAID LVs will be processed.");
+ } else if (strcmp(activation_mode, "complete")) {
+ log_error("Invalid activation mode given.");
+ return EINVALID_CMD_LINE;
}
if (arg_count(cmd, ignorelockingfailure_ARG) || arg_count(cmd, sysinit_ARG))
diff --git a/tools/toollib.c b/tools/toollib.c
index d4c915d..34db90c 100644
--- a/tools/toollib.c
+++ b/tools/toollib.c
@@ -1431,7 +1431,8 @@ int lv_change_activate(struct cmd_context *cmd, struct logical_volume *lv,
int lv_refresh(struct cmd_context *cmd, struct logical_volume *lv)
{
if (!cmd->partial_activation && (lv->status & PARTIAL_LV)) {
- log_error("Refusing refresh of partial LV %s. Use --partial to override.",
+ log_error("Refusing refresh of partial LV %s."
+ " Use '--activationmode partial' to override.",
lv->name);
return 0;
}
More information about the lvm-devel
mailing list