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samba-mirror/ctdb/tools/ctdb_natgw
Martin Schwenke 16b848553d ctdb: Change NAT gateway to use leader/follower
Instead of master/slave.

Nearly all of these are simple textual substitutions, which preserve
the case of the original.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>
2020-07-24 08:37:31 +00:00

195 lines
4.8 KiB
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#!/bin/sh
if [ -z "$CTDB_BASE" ] ; then
export CTDB_BASE="/usr/local/etc/ctdb"
fi
. "${CTDB_BASE}/functions"
load_script_options "failover" "11.natgw"
# Default NAT gateway nodes file location
[ -n "$CTDB_NATGW_NODES" ] || CTDB_NATGW_NODES="${CTDB_BASE}/natgw_nodes"
if [ -z "$CTDB" ] ; then
CTDB=ctdb
fi
############################################################
usage ()
{
cat <<EOF
$0 <option>
<option> is one of:
leader Display node number and private IP address of leader node
list List private IP addresses of nodes in group, annotate leader
status Show status of nodes in NAT gateway group
EOF
exit 1
}
nodestatus_X=""
# Fields are:
# Node|IP|Disconnected|Banned|Disabled|Unhealthy|Stopped|Inactive|PartiallyOnline|ThisNode
get_nodestatus_X ()
{
# Result is cached in global variable nodestatus_X
[ -n "$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)
[ $? -ne 255 ] # ctdb nodestatus returns 255 on failure
}
get_natgw_nodes ()
{
# Result is cached in global variable natgw_nodes
if [ -n "$natgw_nodes" ] ; then
return
fi
if [ ! -r "$CTDB_NATGW_NODES" ] ; then
return 1
fi
natgw_nodes=$(cat "$CTDB_NATGW_NODES") || return 1
# Sanity check file contents here
while read _ip _options ; do
# Skip comments
case "$_ip" in
\#*) continue ;;
esac
case "$_options" in
follower-only|"") : ;;
*) die "${prog}: Invalid options \"${_options}\" in \"$CTDB_NATGW_NODES\""
esac
done <<EOF
$natgw_nodes
EOF
return 0
}
# Print the PNN and IP address of the NAT gateway leader node
find_leader ()
{
get_natgw_nodes || \
die "${prog}: NAT gateway nodes file \"$CTDB_NATGW_NODES\" not found"
get_nodestatus_X || \
die "${prog}: Unable to get status of nodes"
# $_ms is an @-delimited list of nodes that are allowed to be the leader
_ms="@"
while read _ip _options ; do
case "$_options" in
"") _ms="${_ms}${_ip}@" ;;
esac
done <<EOF
$natgw_nodes
EOF
# Now filter by $ms and by status of nodes...
# Note that the 3 awk invocations below have "||" between them, so
# the first to succeed will select the leader node.
# First try for a fully active and healthy node, so must not be
# DISABLED, UNHEALTHY or INACTIVE (last covers DISCONNECTED,
# BANNED or STOPPED)
awk -F '|' -v ms="$_ms" \
'BEGIN { ret = 2 }
ms ~ "@" $2 "@" &&
$5 == 0 && $6 == 0 && $8 == 0 { print $1, $2 ; ret=0 ; exit }
END { exit ret }' <<EOF ||
$nodestatus_X
EOF
# Not found? UNHEALTHY/BANNED will do, so node must not be
# DISCONNECTED, DISABLED or STOPPED
awk -F '|' -v ms="$_ms" \
'BEGIN { ret = 2 }
ms ~ "@" $2 "@" &&
$3 == 0 && $5 == 0 && $7 == 0 { print $1, $2 ; ret=0 ; exit }
END { exit ret }' <<EOF ||
$nodestatus_X
EOF
# Not found? STOPPED will do, so node must not be DISCONNECTED or
# DISABLED
awk -F '|' -v ms="$_ms" \
'BEGIN { ret = 2 }
ms ~ "@" $2 "@" &&
$3 == 0 && $5 == 0 { print $1, $2 ; ret=0 ; exit }
END { exit ret }' <<EOF
$nodestatus_X
EOF
}
# List all nodes in the NAT gateway group, annotating the leader node
nodes_list ()
{
get_natgw_nodes || \
die "${prog}: NAT gateway nodes file \"$CTDB_NATGW_NODES\" not found"
# Intentional word splitting here
# shellcheck disable=SC2046
set -- $(find_leader) || \
die "${prog}: Unable to determine NAT gateway leader node"
_leader_ip="$2"
# Annotate the leader node
while read _ip _options ; do
if [ "$_ip" = "$_leader_ip" ] ; then
_options="LEADER${_options:+,}${_options}"
fi
# There is no other way to do this and keep shellcheck happy.
# The tab character must be in the format string and the
# format string must contain no variables. Some shells will
# expand a tab if it is in an argument but others won't.
if [ -n "$_options" ] ; then
printf '%s\t%s\n' "$_ip" "$_options"
else
echo "$_ip"
fi
done <<EOF
$natgw_nodes
EOF
}
# Print the status of all nodes in the NAT gateway group, along with a count
nodes_status ()
{
get_natgw_nodes || \
die "${prog}: NAT gateway nodes file \"$CTDB_NATGW_NODES\" not found"
get_nodestatus || \
die "${prog}: Unable to get status of nodes"
# $_ns is a @-delimited list of nodes in the NAT gateway group
_ns="@"
while read _ip _options ; do
_ns="${_ns}${_ip}@"
done <<EOF
$natgw_nodes
EOF
# Print status of nodes in $_ns, along with node count
awk -v ns="$_ns" 'ns ~ "@" $2 "@" { print $0 }' <<EOF
$nodestatus
EOF
}
prog=$(basename "$0")
cmd="$1"
case "$cmd" in
leader) find_leader ;;
list) nodes_list ;;
status) nodes_status ;;
*) usage ;;
esac