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|
#!/bin/sh
# This must run as root as CTDB tool commands need to access CTDB socket
[ $(id -u) -eq 0 ] || exec sudo "$0" "$@"
# this script needs to be installed so that statd points to it with the -H
# command line argument. The easiest way to do that is to put something like this in
# /etc/sysconfig/nfs:
# STATD_HOSTNAME="myhostname -H /etc/ctdb/statd-callout"
[ -n "$CTDB_BASE" ] || \
export CTDB_BASE=$(cd -P $(dirname "$0") ; echo "$PWD")
. $CTDB_BASE/functions
# Overwrite this so we get some logging
die ()
{
script_log "statd-callout" "$@"
exit 1
}
loadconfig ctdb
loadconfig nfs
[ -n "$NFS_HOSTNAME" ] || \
die "NFS_HOSTNAME is not configured. statd-callout failed"
# A handy newline
nl="
"
case "$1" in
add-client)
# statd does not tell us to which IP the client connected so
# we must add it to all the IPs that we serve
cip="$2"
pnn=$(ctdb xpnn | sed -e 's/.*://')
date=$(date '+%s')
ctdb ip -Y |
tail -n +2 | {
# This all needs to be in the end of the pipe so it
# doesn't get lost
items=""
while IFS=":" read x sip node x ; do
[ "$node" = "$pnn" ] || continue # not us
key="statd-state@${sip}@${cip}"
item="\"${key}\" \"${date}\""
items="${items}${items:+${nl}}${item}"
done
if ! echo "$items" | ctdb ptrans "ctdb.tdb" ; then
die "Failed to add clients"
fi
}
;;
del-client)
# statd does not tell us from which IP the client disconnected
# so we must add it to all the IPs that we serve
cip="$2"
pnn=$(ctdb xpnn | sed -e 's/.*://')
ctdb ip -Y |
tail -n +2 | {
# This all needs to be in the end of the pipe so it
# doesn't get lost
items=""
while IFS=":" read x sip node x ; do
[ "$node" = "$pnn" ] || continue # not us
key="statd-state@${sip}@${cip}"
item="\"${key}\" \"\""
items="${items}${items:+${nl}}${item}"
done
if ! echo "$items" | ctdb ptrans "ctdb.tdb" ; then
die "Failed to delete clients"
fi
}
;;
notify)
# we must restart the lockmanager (on all nodes) so that we get
# a clusterwide grace period (so other clients dont take out
# conflicting locks through other nodes before all locks have been
# reclaimed)
# we need these settings to make sure that no tcp connections survive
# across a very fast failover/failback
#echo 10 > /proc/sys/net/ipv4/tcp_fin_timeout
#echo 0 > /proc/sys/net/ipv4/tcp_max_tw_buckets
#echo 0 > /proc/sys/net/ipv4/tcp_max_orphans
# Delete the notification list for statd, we dont want it to
# ping any clients
rm -f /var/lib/nfs/statd/sm/*
rm -f /var/lib/nfs/statd/sm.bak/*
# we must keep a monotonically increasing state variable for the entire
# cluster so state always increases when ip addresses fail from one
# node to another
# We use epoch and hope the nodes are close enough in clock.
# Even numbers mean service is shut down, odd numbers mean
# service is started.
state_even=$(( $(date '+%s') / 2 * 2))
# we must also let some time pass between stopping and restarting the
# lockmanager since othervise there is a window where the lockmanager
# will respond "strangely" immediately after restarting it, which
# causes clients to fail to reclaim the locks.
#
if [ "${CTDB_NFS_SERVER_MODE:-${NFS_SERVER_MODE}}" != "ganesha" ] ; then
startstop_nfslock stop >/dev/null 2>&1
sleep 2
startstop_nfslock start >/dev/null 2>&1
fi
# we now need to send out additional statd notifications to ensure
# that clients understand that the lockmanager has restarted.
# we have three cases:
# 1, clients that ignore the ip address the stat notification came from
# and ONLY care about the 'name' in the notify packet.
# these clients ONLY work with lock failover IFF that name
# can be resolved into an ipaddress that matches the one used
# to mount the share. (==linux clients)
# This is handled when starting lockmanager above, but those
# packets are sent from the "wrong" ip address, something linux
# clients are ok with, buth other clients will barf at.
# 2, Some clients only accept statd packets IFF they come from the
# 'correct' ip address.
# 2a,Send out the notification using the 'correct' ip address and also
# specify the 'correct' hostname in the statd packet.
# Some clients require both the correct source address and also the
# correct name. (these clients also ONLY work if the ip addresses
# used to map the share can be resolved into the name returned in
# the notify packet.)
# 2b,Other clients require that the source ip address of the notify
# packet matches the ip address used to take out the lock.
# I.e. that the correct source address is used.
# These clients also require that the statd notify packet contains
# the name as the ip address used when the lock was taken out.
#
# Both 2a and 2b are commonly used in lockmanagers since they maximize
# probability that the client will accept the statd notify packet and
# not just ignore it.
# For all IPs we serve, collect info and push to the config database
pnn=$(ctdb xpnn | sed -e 's/.*://')
# Construct a sed expression to take catdb output and produce pairs of:
# server-IP client-IP
# but only for the server-IPs that are hosted on this node.
sed_expr=$(ctdb ip | tail -n +2 |
awk -v pnn=$pnn 'pnn == $2 { printf "s/^key.*=.*statd-state@\\(%s\\)@\\([^\"]*\\).*/\\1 \\2/p\n", gensub(/\./, "\\\\.", "g", $1) }')
statd_state=$(ctdb catdb ctdb.tdb | sed -n "$sed_expr" | sort)
[ -n "$statd_state" ] || exit 0
# The following is dangerous if this script times out before
# all of the smnotify commands are run. Revert to individual
# pdelete commands for now and consider optimising smnotify to
# read all the data from stdin and then run it in the
# background.
#
# Delete all the items from the TDB
#if ! echo "$statd_state" | \
# awk '{ printf "\"statd-state@%s@%s\" \"\"\n", $1, $2 }') | \
# ctdb ptrans ctdb.tdb ; then
# die "Yikes!"
#fi
prev=""
echo "$statd_state" |
while read sip cip ; do
# Delete the entry from the DB
ctdb pdelete ctdb.tdb "statd-state@${sip}@${cip}"
# Reset stateval for each serverip
[ "$sip" = "$prev" ] || stateval="$state_even"
# Send notifies for server shutdown
smnotify --client=$cip --ip=$sip --server=$sip --stateval=$stateval
smnotify --client=$cip --ip=$sip --server=$NFS_HOSTNAME --stateval=$stateval
# Send notifies for server startup
stateval=$(($stateval + 1))
smnotify --client=$cip --ip=$sip --server=$sip --stateval=$stateval
smnotify --client=$cip --ip=$sip --server=$NFS_HOSTNAME --stateval=$stateval
done
;;
esac
|
