Attachment 14893 Details for Bug 13800 – Patch for 4.10

[patch] Patch for 4.10

BZ13800-4.10.patch (text/plain), 16.86 KB, created by Martin Schwenke on 2019-03-02 09:43:23 UTC

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Creator: Martin Schwenke

Created: 2019-03-02 09:43:23 UTC

Size: 16.86 KB

patch

obsolete

>From 404d4cf2032a7e932b12932e4bac0b87c4df6141 Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Mon, 21 Jan 2019 16:28:28 +1100
>Subject: [PATCH 1/9] ctdb-recoverd: Free cluster mutex handler on failure to
> take lock
>
>If nested events occur while the file descriptor handler is still
>active then chaos can ensue.  For example, if a node is banned and the
>lock is explicitly cancelled (e.g. due to election loss) then
>double-talloc-free()s abound.
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>(cherry picked from commit 621658cbed5d91d7096fc208bac2ff93a1880e7d)
>---
> ctdb/server/ctdb_recoverd.c | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)
>
>diff --git a/ctdb/server/ctdb_recoverd.c b/ctdb/server/ctdb_recoverd.c
>index 578127a4514..a63021e4d8b 100644
>--- a/ctdb/server/ctdb_recoverd.c
>+++ b/ctdb/server/ctdb_recoverd.c
>@@ -897,6 +897,16 @@ static void take_reclock_handler(char status,
> 	struct ctdb_recovery_lock_handle *s =
> 		(struct ctdb_recovery_lock_handle *) private_data;
> 
>+	s->locked = (status == '0') ;
>+
>+	/*
>+	 * If unsuccessful then ensure the process has exited and that
>+	 * the file descriptor event handler has been cancelled
>+	 */
>+	if (! s->locked) {
>+		TALLOC_FREE(s->h);
>+	}
>+
> 	switch (status) {
> 	case '0':
> 		s->latency = latency;
>@@ -912,7 +922,6 @@ static void take_reclock_handler(char status,
> 	}
> 
> 	s->done = true;
>-	s->locked = (status == '0') ;
> }
> 
> static void force_election(struct ctdb_recoverd *rec,
>-- 
>2.20.1
>
>
>From ba24f974d9ecefe14a247ce01726b037cfdec878 Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Mon, 21 Jan 2019 16:36:13 +1100
>Subject: [PATCH 2/9] ctdb-recoverd: Clean up logging on failure to take
> recovery lock
>
>Add an explicit case for a timeout and clean up the other messages.
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>(cherry picked from commit 7e4aae6943291c3144c8a3ff97537e8d4c7dc7c9)
>---
> ctdb/server/ctdb_recoverd.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
>diff --git a/ctdb/server/ctdb_recoverd.c b/ctdb/server/ctdb_recoverd.c
>index a63021e4d8b..473e6cbe8cc 100644
>--- a/ctdb/server/ctdb_recoverd.c
>+++ b/ctdb/server/ctdb_recoverd.c
>@@ -913,12 +913,15 @@ static void take_reclock_handler(char status,
> 		break;
> 
> 	case '1':
>-		DEBUG(DEBUG_ERR,
>-		      ("Unable to take recovery lock - contention\n"));
>+		D_ERR("Unable to take recovery lock - contention\n");
>+		break;
>+
>+	case '2':
>+		D_ERR("Unable to take recovery lock - timeout\n");
> 		break;
> 
> 	default:
>-		DEBUG(DEBUG_ERR, ("ERROR: when taking recovery lock\n"));
>+		D_ERR("Unable to take recover lock - unknown error\n");
> 	}
> 
> 	s->done = true;
>-- 
>2.20.1
>
>
>From 5efce3581b3bf5d8d5fd7af371c722234b28da57 Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Thu, 10 Jan 2019 13:24:34 +1100
>Subject: [PATCH 3/9] ctdb-recoverd: Make recoverd context available in
> recovery lock handle
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>(cherry picked from commit c0fb62ed3954fc6e8667480aba92003fc270f257)
>---
> ctdb/server/ctdb_recoverd.c | 3 +++
> 1 file changed, 3 insertions(+)
>
>diff --git a/ctdb/server/ctdb_recoverd.c b/ctdb/server/ctdb_recoverd.c
>index 473e6cbe8cc..c3beac7d18b 100644
>--- a/ctdb/server/ctdb_recoverd.c
>+++ b/ctdb/server/ctdb_recoverd.c
>@@ -888,6 +888,7 @@ struct ctdb_recovery_lock_handle {
> 	bool locked;
> 	double latency;
> 	struct ctdb_cluster_mutex_handle *h;
>+	struct ctdb_recoverd *rec;
> };
> 
> static void take_reclock_handler(char status,
>@@ -954,6 +955,8 @@ static bool ctdb_recovery_lock(struct ctdb_recoverd *rec)
> 		return false;
> 	};
> 
>+	s->rec = rec;
>+
> 	h = ctdb_cluster_mutex(s,
> 			       ctdb,
> 			       ctdb->recovery_lock,
>-- 
>2.20.1
>
>
>From 5a666176f415b10b7b15c4a036da1784a888fbca Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Thu, 10 Jan 2019 14:01:57 +1100
>Subject: [PATCH 4/9] ctdb-recoverd: Ban node on unknown error when taking
> recovery lock
>
>We really shouldn't see unknown errors.  They probably represent a
>misconfigured recovery lock or similar.
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>(cherry picked from commit 45a77d65b2e39b4af94da4ab99575f4ee08a7ebd)
>---
> ctdb/server/ctdb_recoverd.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
>diff --git a/ctdb/server/ctdb_recoverd.c b/ctdb/server/ctdb_recoverd.c
>index c3beac7d18b..584d65d61a7 100644
>--- a/ctdb/server/ctdb_recoverd.c
>+++ b/ctdb/server/ctdb_recoverd.c
>@@ -923,6 +923,17 @@ static void take_reclock_handler(char status,
> 
> 	default:
> 		D_ERR("Unable to take recover lock - unknown error\n");
>+
>+		{
>+			struct ctdb_recoverd *rec = s->rec;
>+			struct ctdb_context *ctdb = rec->ctdb;
>+			uint32_t pnn = ctdb_get_pnn(ctdb);
>+
>+			D_ERR("Banning this node\n");
>+			ctdb_ban_node(rec,
>+				      pnn,
>+				      ctdb->tunable.recovery_ban_period);
>+		}
> 	}
> 
> 	s->done = true;
>-- 
>2.20.1
>
>
>From aa3c6ec12677abf3c847810fd249acf2b8b5c609 Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Fri, 22 Feb 2019 15:09:33 +1100
>Subject: [PATCH 5/9] ctdb-recoverd: Time out attempt to take recovery lock
> after 120s
>
>Currently this will wait forever.  It really needs a timeout in case
>the cluster filesystem (or other lock mechanism) is completely wedged.
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>(cherry picked from commit 13a1a4808935290dceb219daccd7aac3fda4e184)
>---
> ctdb/server/ctdb_recoverd.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/ctdb/server/ctdb_recoverd.c b/ctdb/server/ctdb_recoverd.c
>index 584d65d61a7..9b3559b2a92 100644
>--- a/ctdb/server/ctdb_recoverd.c
>+++ b/ctdb/server/ctdb_recoverd.c
>@@ -971,7 +971,7 @@ static bool ctdb_recovery_lock(struct ctdb_recoverd *rec)
> 	h = ctdb_cluster_mutex(s,
> 			       ctdb,
> 			       ctdb->recovery_lock,
>-			       0,
>+			       120,
> 			       take_reclock_handler,
> 			       s,
> 			       lost_reclock_handler,
>-- 
>2.20.1
>
>
>From cb33080209e473aaf396ece15a2ce6215e0e3684 Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Mon, 21 Jan 2019 12:13:08 +1100
>Subject: [PATCH 6/9] ctdb-tests: Force test failure if local daemon setup
> fails
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>(cherry picked from commit ce09d9c3e4c72ebec7a21686ae913398a5c9020f)
>---
> ctdb/tests/simple/scripts/local_daemons.bash | 3 +++
> 1 file changed, 3 insertions(+)
>
>diff --git a/ctdb/tests/simple/scripts/local_daemons.bash b/ctdb/tests/simple/scripts/local_daemons.bash
>index cf6671757b3..5d07b1f6398 100644
>--- a/ctdb/tests/simple/scripts/local_daemons.bash
>+++ b/ctdb/tests/simple/scripts/local_daemons.bash
>@@ -34,6 +34,9 @@ setup_ctdb ()
> 		${public_addresses:+-P} ${public_addresses} \
> 		${CTDB_USE_IPV6:+-6} \
> 		${TEST_SOCKET_WRAPPER_SO_PATH:+-S} ${TEST_SOCKET_WRAPPER_SO_PATH}
>+	if [ $? -ne 0 ] ; then
>+		exit 1
>+	fi
> 
> 	local pnn
> 	for pnn in $(seq 0 $(($TEST_LOCAL_DAEMONS - 1))) ; do
>-- 
>2.20.1
>
>
>From 737b578fd9c412364c9d82758324cdc7f4b4479b Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Mon, 21 Jan 2019 12:13:29 +1100
>Subject: [PATCH 7/9] ctdb-tests: Add -R option for local daemons to use
> recovery lock command
>
>Under the covers, a command is always used.  However, there is no way
>of testing of the code path where a command is explicitly configured.
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>(cherry picked from commit e74f5243fcb7594939769c16f3c79ab167dd1227)
>---
> ctdb/tests/local_daemons.sh | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
>diff --git a/ctdb/tests/local_daemons.sh b/ctdb/tests/local_daemons.sh
>index 9329a60643c..07cf1e9b135 100755
>--- a/ctdb/tests/local_daemons.sh
>+++ b/ctdb/tests/local_daemons.sh
>@@ -132,6 +132,7 @@ Options:
>   -N <file>     Nodes file (default: automatically generated)
>   -n <num>      Number of nodes (default: 3)
>   -P <file>     Public addresses file (default: automatically generated)
>+  -R            Use a command for the recovery lock (default: use a file)
>   -S <library>  Socket wrapper shared library to preload (default: none)
>   -6            Generate IPv6 IPs for nodes, public addresses (default: IPv4)
> EOF
>@@ -145,17 +146,19 @@ local_daemons_setup ()
> 	_nodes_file=""
> 	_num_nodes=3
> 	_public_addresses_file=""
>+	_recovery_lock_use_command=false
> 	_socket_wrapper=""
> 	_use_ipv6=false
> 
> 	set -e
> 
>-	while getopts "FN:n:P:S:6h?" _opt ; do
>+	while getopts "FN:n:P:RS:6h?" _opt ; do
> 		case "$_opt" in
> 		F) _disable_failover=true ;;
> 		N) _nodes_file="$OPTARG" ;;
> 		n) _num_nodes="$OPTARG" ;;
> 		P) _public_addresses_file="$OPTARG" ;;
>+		R) _recovery_lock_use_command=true ;;
> 		S) _socket_wrapper="$OPTARG" ;;
> 		6) _use_ipv6=true ;;
> 		\?|h) local_daemons_setup_usage ;;
>@@ -188,6 +191,11 @@ local_daemons_setup ()
> 				       $_use_ipv6 >"$_public_addresses_all"
> 	fi
> 
>+	_recovery_lock="${directory}/rec.lock"
>+	if $_recovery_lock_use_command ; then
>+		_recovery_lock="! ${CTDB_CLUSTER_MUTEX_HELPER} ${_recovery_lock}"
>+	fi
>+
> 	if [ -n "$_socket_wrapper" ] ; then
> 		setup_socket_wrapper "$_socket_wrapper"
> 	fi
>@@ -221,7 +229,7 @@ local_daemons_setup ()
> 	log level = INFO
> 
> [cluster]
>-	recovery lock = ${directory}/rec.lock
>+	recovery lock = ${_recovery_lock}
> 	node address = ${_node_ip}
> 
> [database]
>-- 
>2.20.1
>
>
>From a1c548f3b314fdbd55293ff2249745fec429244c Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Mon, 21 Jan 2019 12:15:33 +1100
>Subject: [PATCH 8/9] ctdb-tests: Add a test for configuring the recovery lock
> as a command
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>(cherry picked from commit ebc082122fb34ffb8cbcafde9ad39bcc241d33ed)
>---
> ctdb/tests/simple/01_ctdb_reclock_command.sh | 28 ++++++++++++++++++++
> ctdb/tests/simple/scripts/local_daemons.bash |  3 +++
> 2 files changed, 31 insertions(+)
> create mode 100755 ctdb/tests/simple/01_ctdb_reclock_command.sh
>
>diff --git a/ctdb/tests/simple/01_ctdb_reclock_command.sh b/ctdb/tests/simple/01_ctdb_reclock_command.sh
>new file mode 100755
>index 00000000000..34f82e981a1
>--- /dev/null
>+++ b/ctdb/tests/simple/01_ctdb_reclock_command.sh
>@@ -0,0 +1,28 @@
>+#!/bin/bash
>+
>+test_info()
>+{
>+    cat <<EOF
>+Check that CTDB operates correctly if the recovery lock is configured
>+as a command.
>+
>+This test only does anything with local daemons.  On a real cluster it
>+has no way of updating configuration.
>+EOF
>+}
>+
>+. "${TEST_SCRIPTS_DIR}/integration.bash"
>+
>+set -e
>+
>+if [ -z "$TEST_LOCAL_DAEMONS" ] ; then
>+	echo "SKIPPING this test - only runs against local daemons"
>+	exit 0
>+fi
>+
>+echo "Starting CTDB with recovery lock command configured..."
>+ctdb_test_init --reclock-use-command
>+
>+cluster_is_healthy
>+
>+echo "Good, that seems to work!"
>diff --git a/ctdb/tests/simple/scripts/local_daemons.bash b/ctdb/tests/simple/scripts/local_daemons.bash
>index 5d07b1f6398..5da900288b2 100644
>--- a/ctdb/tests/simple/scripts/local_daemons.bash
>+++ b/ctdb/tests/simple/scripts/local_daemons.bash
>@@ -22,10 +22,12 @@ setup_ctdb ()
> 	local public_addresses=""
> 	local no_event_scripts=false
> 	local disable_failover=""
>+	local reclock_use_command=""
> 	case "$1" in
> 	--no-public-addresses) public_addresses="/dev/null" ;;
> 	--no-event-scripts)    no_event_scripts=true    ;;
> 	--disable-failover)    disable_failover="yes"   ;;
>+	--reclock-use-command) reclock_use_command="yes" ;;
> 	esac
> 
> 	$ctdb_local_daemons setup \
>@@ -33,6 +35,7 @@ setup_ctdb ()
> 		${disable_failover:+-F} \
> 		${public_addresses:+-P} ${public_addresses} \
> 		${CTDB_USE_IPV6:+-6} \
>+		${reclock_use_command:+-R} \
> 		${TEST_SOCKET_WRAPPER_SO_PATH:+-S} ${TEST_SOCKET_WRAPPER_SO_PATH}
> 	if [ $? -ne 0 ] ; then
> 		exit 1
>-- 
>2.20.1
>
>
>From d5131afc533102ed5adfb147bf1a316e51810729 Mon Sep 17 00:00:00 2001
>From: Martin Schwenke <martin@meltin.net>
>Date: Mon, 21 Jan 2019 12:16:43 +1100
>Subject: [PATCH 9/9] ctdb-cluster-mutex: Separate out command and file
> handling
>
>This code is difficult to read and there really is no common code
>between the 2 cases.  For example, there is no need to split a
>filename into words.  Separating each of the 2 cases into its own
>function makes the logic much easier to understand.
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13800
>
>Signed-off-by: Martin Schwenke <martin@meltin.net>
>Reviewed-by: Amitay Isaacs <amitay@gmail.com>
>
>Autobuild-User(master): Amitay Isaacs <amitay@samba.org>
>Autobuild-Date(master): Mon Feb 25 03:40:16 CET 2019 on sn-devel-144
>
>(cherry picked from commit c93430fe8fe530a55b9a04cf6cc660c3d420e333)
>---
> ctdb/server/ctdb_cluster_mutex.c | 113 +++++++++++++++++++------------
> 1 file changed, 71 insertions(+), 42 deletions(-)
>
>diff --git a/ctdb/server/ctdb_cluster_mutex.c b/ctdb/server/ctdb_cluster_mutex.c
>index 330d5fd1d90..2e3cb8112ad 100644
>--- a/ctdb/server/ctdb_cluster_mutex.c
>+++ b/ctdb/server/ctdb_cluster_mutex.c
>@@ -118,72 +118,101 @@ static void cluster_mutex_handler(struct tevent_context *ev,
> 
> static char cluster_mutex_helper[PATH_MAX+1] = "";
> 
>-static bool cluster_mutex_helper_args(TALLOC_CTX *mem_ctx,
>-				      const char *argstring, char ***argv)
>+static bool cluster_mutex_helper_args_file(TALLOC_CTX *mem_ctx,
>+					   const char *argstring,
>+					   char ***argv)
> {
>-	int nargs, i, ret, n;
>-	bool is_command = false;
>+	bool ok;
> 	char **args = NULL;
>-	char *strv = NULL;
>-	char *t = NULL;
> 
>-	if (argstring != NULL && argstring[0] == '!') {
>-		/* This is actually a full command */
>-		is_command = true;
>-		t = discard_const(&argstring[1]);
>-	} else {
>-		is_command = false;
>-		t = discard_const(argstring);
>+	ok = ctdb_set_helper("cluster mutex helper",
>+			     cluster_mutex_helper,
>+			     sizeof(cluster_mutex_helper),
>+			     "CTDB_CLUSTER_MUTEX_HELPER",
>+			     CTDB_HELPER_BINDIR,
>+			     "ctdb_mutex_fcntl_helper");
>+	if (! ok) {
>+		DBG_ERR("ctdb exiting with error: "
>+			"Unable to set cluster mutex helper\n");
>+		exit(1);
> 	}
> 
>-	ret = strv_split(mem_ctx, &strv, t, " \t");
>-	if (ret != 0) {
>-		DEBUG(DEBUG_ERR,
>-		      ("Unable to parse mutex helper string \"%s\" (%s)\n",
>-		       argstring, strerror(ret)));
>+
>+	/* Array includes default helper, file and NULL */
>+	args = talloc_array(mem_ctx, char *, 3);
>+	if (args == NULL) {
>+		DBG_ERR("Memory allocation error\n");
> 		return false;
> 	}
>-	n = strv_count(strv);
> 
>-	args = talloc_array(mem_ctx, char *, n + (is_command ? 1 : 2));
>+	args[0] = cluster_mutex_helper;
> 
>-	if (args == NULL) {
>-		DEBUG(DEBUG_ERR,(__location__ " out of memory\n"));
>+	args[1] = talloc_strdup(args, argstring);
>+	if (args[1] == NULL) {
>+		DBG_ERR("Memory allocation error\n");
> 		return false;
> 	}
> 
>-	nargs = 0;
>-
>-	if (! is_command) {
>-		if (!ctdb_set_helper("cluster mutex helper",
>-				     cluster_mutex_helper,
>-				     sizeof(cluster_mutex_helper),
>-				     "CTDB_CLUSTER_MUTEX_HELPER",
>-				     CTDB_HELPER_BINDIR,
>-				     "ctdb_mutex_fcntl_helper")) {
>-			DEBUG(DEBUG_ERR,("ctdb exiting with error: %s\n",
>-					 __location__
>-					 " Unable to set cluster mutex helper\n"));
>-			exit(1);
>-		}
>+	args[2] = NULL;
>+
>+	*argv = args;
>+	return true;
>+}
> 
>-		args[nargs++] = cluster_mutex_helper;
>+static bool cluster_mutex_helper_args_cmd(TALLOC_CTX *mem_ctx,
>+					  const char *argstring,
>+					  char ***argv)
>+{
>+	int i, ret, n;
>+	char **args = NULL;
>+	char *strv = NULL;
>+	char *t = NULL;
>+
>+	ret = strv_split(mem_ctx, &strv, argstring, " \t");
>+	if (ret != 0) {
>+		D_ERR("Unable to parse mutex helper command \"%s\" (%s)\n",
>+		      argstring,
>+		      strerror(ret));
>+		return false;
> 	}
>+	n = strv_count(strv);
>+
>+	/* Extra slot for NULL */
>+	args = talloc_array(mem_ctx, char *, n + 1);
>+	if (args == NULL) {
>+		DBG_ERR("Memory allocation error\n");
>+		return false;
>+	}
>+
>+	talloc_steal(args, strv);
> 
> 	t = NULL;
>-	for (i = 0; i < n; i++) {
>-		/* Don't copy, just keep cmd_args around */
>+	for (i = 0 ; i < n; i++) {
> 		t = strv_next(strv, t);
>-		args[nargs++] = t;
>+		args[i] = t;
> 	}
> 
>-	/* Make sure last argument is NULL */
>-	args[nargs] = NULL;
>+	args[n] = NULL;
> 
> 	*argv = args;
> 	return true;
> }
> 
>+static bool cluster_mutex_helper_args(TALLOC_CTX *mem_ctx,
>+				      const char *argstring,
>+				      char ***argv)
>+{
>+	bool ok;
>+
>+	if (argstring != NULL && argstring[0] == '!') {
>+		ok = cluster_mutex_helper_args_cmd(mem_ctx, &argstring[1], argv);
>+	} else {
>+		ok = cluster_mutex_helper_args_file(mem_ctx, argstring, argv);
>+	}
>+
>+	return ok;
>+}
>+
> struct ctdb_cluster_mutex_handle *
> ctdb_cluster_mutex(TALLOC_CTX *mem_ctx,
> 		   struct ctdb_context *ctdb,
>-- 
>2.20.1
>

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