config: add interface_modify.sh and call it under flock to make modification on inter...

[sahlberg/ctdb.git] / config / interface_modify.sh

diff --git a/config/interface_modify.sh b/config/interface_modify.sh
new file mode 100755 (executable)
index 0000000..3ac7fe8
--- /dev/null
+++ b/config/interface_modify.sh
@@ -0,0 +1,73 @@
+#!/bin/sh
+#
+
+OP=$1
+IFACE=$2
+IP=$3
+MASKBITS=$4
+
+add_ip_to_iface()
+{
+       local _iface=$1
+       local _ip=$2
+       local _maskbits=$3
+
+       # we make sure the interface is up first
+       /sbin/ip link set $_iface up || {
+               echo "Failed to bringup interface $_iface"
+               return 1;
+       }
+       /sbin/ip addr add $_ip/$_maskbits brd + dev $_iface || {
+               echo "Failed to add $_ip/$_maskbits on dev $_iface"
+               return 1;
+       }
+
+       return 0;
+}
+
+delete_ip_from_iface()
+{
+       local _iface=$1
+       local _ip=$2
+       local _maskbits=$3
+
+       # the ip tool will delete all secondary IPs if this is the primary. To work around
+       # this _very_ annoying behaviour we have to keep a record of the secondaries and re-add
+       # them afterwards. yuck
+       local _secondaries=""
+       if /sbin/ip addr list dev $_iface primary | grep -q "inet $_ip/$_maskbits " ; then
+           _secondaries=`/sbin/ip addr list dev $_iface secondary | grep " inet " | awk '{print $2}'`
+       fi
+       local _failed=0
+       /sbin/ip addr del $_ip/$_maskbits dev $_iface || _failed=1
+       [ -z "$_secondaries" ] || {
+           local _i=""
+           for _i in $_secondaries; do
+               if /sbin/ip addr list dev $_iface | grep -q "inet $_i" ; then
+                   echo "kept secondary $_i on dev $_iface"
+               else
+                   echo "re-adding secondary address $_i to dev $_iface"
+                   /sbin/ip addr add $_i dev $_iface || _failed=1
+               fi
+           done
+       }
+       [ $_failed = 0 ] || {
+               echo "Failed to del $_ip on dev $_iface"
+               return 1;
+       }
+       return 0;
+}
+
+case "$OP" in
+       add)
+               add_ip_to_iface $IFACE $IP $MASKBITS
+               exit $?
+               ;;
+       delete)
+               delete_ip_from_iface $IFACE $IP $MASKBITS
+               exit $?
+               ;;
+esac
+
+echo "$0: unknown operation[$OP]"
+exit 1