ctdb-tools: Add new ctdb_lvs helper

This will replace the ctdb CLI tool "lvs" and "lvsmaster" options.  It
also makes LVS daemon support unnecessary.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>

3 files changed, 228 insertions, 0 deletions

diff --git a/ctdb/packaging/RPM/ctdb.spec.in b/ctdb/packaging/RPM/ctdb.spec.in
index bbbf66c26b1..19c2af19e5e 100644
--- a/ctdb/packaging/RPM/ctdb.spec.in
+++ b/ctdb/packaging/RPM/ctdb.spec.in
@@ -205,6 +205,7 @@ rm -rf $RPM_BUILD_ROOT
 %{_libexecdir}/ctdb/ctdb_event_helper
 %{_libexecdir}/ctdb/ctdb_recovery_helper
 %{_libexecdir}/ctdb/ctdb_natgw
+%{_libexecdir}/ctdb/ctdb_lvs
 %{_libexecdir}/ctdb/ctdb_killtcp
 %{_libexecdir}/ctdb/smnotify
 %dir %{_libdir}
diff --git a/ctdb/tools/ctdb_lvs b/ctdb/tools/ctdb_lvs
new file mode 100755
index 00000000000..b71a3d47df8
--- /dev/null
+++ b/ctdb/tools/ctdb_lvs
@@ -0,0 +1,220 @@
+#!/bin/sh
+
+if [ -z "$CTDB_BASE" ] ; then
+	export CTDB_BASE="/usr/local/etc/ctdb"
+fi
+
+. "${CTDB_BASE}/functions"
+loadconfig "ctdb"
+
+# Default LVS nodes file location
+[ -n "$CTDB_LVS_NODES" ] || CTDB_LVS_NODES="${CTDB_BASE}/lvs_nodes"
+
+[ -n "$CTDB_SOCKET" ] && export CTDB_SOCKET
+
+############################################################
+
+usage ()
+{
+	cat <<EOF
+$0 <option>
+
+<option> is one of:
+  master     Display node number of master node
+  list       List node number and private IP address of usable nodes in group
+  status     Show status of all nodes in LVS group
+EOF
+    exit 1
+}
+
+nodestatus_X=""
+# Fields are:
+# Node|IP|Disconnected|Banned|Disabled|Unhealthy|Stopped|Inactive|PartiallyOnline|ThisNode
+get_nodestatus_X ()
+{
+	# Result is cached in global variable nodestatus_X
+	[ -n "$nodestatus_X" ] || \
+		nodestatus_X=$(ctdb -X nodestatus all |
+			       sed -e '1d' -e 's@^|@@' -e 's@|$@@')
+}
+
+get_nodestatus ()
+{
+	# Result is cached in global variable nodestatus
+	[ -n "$nodestatus" ] || nodestatus=$(ctdb nodestatus all)
+	case $? in
+	# ctdb nodestatus returns 255 on failure
+	0|255) return 0 ;;
+	*)     return 1 ;;
+	esac
+}
+
+get_lvs_nodes ()
+{
+	# Result is cached in global variable lvs_nodes
+	if [ -n "$lvs_nodes" ] ; then
+		return
+	fi
+
+	if [ ! -r "$CTDB_LVS_NODES" ] ; then
+		return 1
+	fi
+
+	lvs_nodes=$(cat "$CTDB_LVS_NODES") || return 1
+
+	# Sanity check file contents here
+	while read _ip _options ; do
+		# Skip comments
+		case "$_ip" in
+		\#*) continue ;;
+		esac
+		case "$_options" in
+		slave-only|"") : ;;
+		*) die "${prog}: Invalid options \"${_options}\" in  \"$CTDB_LVS_NODES\""
+		esac
+	done <<EOF
+$lvs_nodes
+EOF
+
+	return 0
+}
+
+# Print PNN and IP address of given nodes meeting the criteria for
+# usable LVS nodes.  That is, either those that are healthy or, if no
+# healthy nodes, then nodes that are active and not-disabled.
+# Return codes: 0 = nodes found, 255 = no nodes found, 10 = error.
+filter_nodes ()
+{
+	# $_ns is an @-delimited list of nodes to be considered
+	_ns="$1"
+
+	get_nodestatus_X
+	[ -n "$nodestatus_X" ] || return 10
+
+	# Now filter by $_ns and by status of nodes...
+
+	# Note that the 2 awk invocations below have "||" between
+	# them, so the first to succeed will print the nodes.
+
+	# First try for a fully active and healthy node, so must not
+	# be DISABLED, UNHEALTHY or INACTIVE (last covers
+	# DISCONNECTED, BANNED or STOPPED)
+	awk -F '|' -v ns="$_ns" '
+		BEGIN { ret = 255 }
+		ns ~ "@" $2 "@" && $5 == 0 && $6 == 0 && $8 == 0 {
+			print $1, $2 ; ret=0
+		}
+		END { exit ret }
+		' <<EOF ||
+$nodestatus_X
+EOF
+	# Not found?  UNHEALTHY do, so node must not be INACTIVE or
+	# DISABLED
+	awk -F '|' -v ns="$_ns" '
+		BEGIN { ret = 255 }
+		ns ~ "@" $2 "@" && $5 == 0 && $8 == 0 {
+			print $1, $2 ; ret=0
+		}
+		END { exit ret }
+		' <<EOF
+$nodestatus_X
+EOF
+}
+
+# Print the PNN of the LVS master node
+find_master ()
+{
+	get_lvs_nodes || \
+		die "${prog}: LVS nodes file \"$CTDB_LVS_NODES\" not found"
+
+	# $_ms is an @-delimited list of nodes that are allowed to be the master
+	_ms="@"
+	while read _ip _options ; do
+		case "$_options" in
+		"") _ms="${_ms}${_ip}@" ;;
+		esac
+	done <<EOF
+$lvs_nodes
+EOF
+
+	_master_candidates=$(filter_nodes "$_ms") || return $?
+	echo "${_master_candidates%% *}"
+}
+
+# Print the PNN of the LVS master node, verbose version
+show_master ()
+{
+	_master_pnn=$(find_master)
+	case "$?" in
+	0)
+		echo "Node ${_master_pnn} is LVS master"
+		exit 0
+		;;
+	255)
+		echo "There is no LVS master"
+		exit 255
+		;;
+	*)
+		exit 10
+		;;
+	esac
+}
+
+# List all usable nodes in the LVS group
+nodes_list ()
+{
+	get_lvs_nodes || \
+		die "${prog}: LVS nodes file \"$CTDB_LVS_NODES\" not found"
+
+	# $_ns is a @-delimited list of nodes in the LVS  group
+	_ns="@"
+	while read _ip _options ; do
+		_ns="${_ns}${_ip}@"
+	done <<EOF
+$lvs_nodes
+EOF
+
+	_usable_nodes=$(filter_nodes "$_ns")
+	case $? in
+	0)   : ;;
+	255) exit 0 ;; # Return 0 even if no usable nodes
+	*)   exit 10 ;;
+	esac
+
+	awk '{ print $1 ":" $2 }'<<EOF
+$_usable_nodes
+EOF
+}
+
+# Print the status of all nodes in the LVS group, along with a count
+nodes_status ()
+{
+	get_lvs_nodes || \
+		die "${prog}: LVS nodes file \"$CTDB_LVS_NODES\" not found"
+	get_nodestatus
+	[ -n "$nodestatus" ] || exit 10
+
+	# $_ns is a @-delimited list of nodes in the LVS  group
+	_ns="@"
+	while read _ip _options ; do
+		_ns="${_ns}${_ip}@"
+	done <<EOF
+$lvs_nodes
+EOF
+
+	# Print status of nodes in $_ns, along with node count
+	awk -v ns="$_ns" 'ns ~ "@" $2 "@" { print }' <<EOF
+$nodestatus
+EOF
+}
+
+# For backward compatibility
+prog=$(basename "$0")
+cmd="$1"
+
+case "$cmd" in
+master) show_master ;;
+list)   nodes_list ;;
+status) nodes_status ;;
+*)      usage ;;
+esac
diff --git a/ctdb/wscript b/ctdb/wscript
index 41048fb8fc8..55b50eda819 100755
--- a/ctdb/wscript
+++ b/ctdb/wscript
@@ -550,6 +550,13 @@ def build(bld):
     bld.INSTALL_FILES('${CTDB_HELPER_BINDIR}', 'ctdb_natgw',
                       destname='ctdb_natgw', chmod=0755)
 
+    bld.SAMBA_GENERATOR('ctdb-lvs',
+                        source='tools/ctdb_lvs',
+                        target='ctdb_lvs',
+                        rule='sed %s ${SRC} > ${TGT}' % (sed_cmdline))
+    bld.INSTALL_FILES('${CTDB_HELPER_BINDIR}', 'ctdb_lvs',
+                      destname='ctdb_lvs', chmod=0755)
+
     bld.SAMBA_GENERATOR('ctdbd-wrapper',
                         source='config/ctdbd_wrapper',
                         target='ctdbd_wrapper',