ctdb-tests: Add a new NFS tickle test for the releasing node

Current NFS and CIFS tickle tests do not test the killtcp
functionality on the releasing node.  2-way killing is done for NFS,
so this test explicitly looks for packets from the releasing node.

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

ctdb/tests/complex/30_nfs_tickle_killtcp.sh

@@ -0,0 +1,69 @@
+#!/bin/bash
+
+test_info()
+{
+    cat <<EOF
+Verify that NFS connections are monitored and that NFS tickles are sent.
+
+Create a connection to the NFS server on a node. Then disable the
+relevant NFS server node and ensure that it sends an appropriate reset
+packet.  The packet must come from the releasing node.
+
+Prerequisites:
+
+* An active CTDB cluster with at least 2 nodes with public addresses.
+
+* Test must be run on a real or virtual cluster rather than against
+  local daemons.
+
+* Test must not be run from a cluster node.
+
+* Cluster nodes must be listening on the NFS TCP port (2049).
+
+Expected results:
+
+* CTDB on the releasing node should correctly send a reset packet when
+  the node is disabled.
+EOF
+}
+
+. "${TEST_SCRIPTS_DIR}/integration.bash"
+
+set -e
+
+ctdb_test_init "$@"
+
+ctdb_test_check_real_cluster
+
+cluster_is_healthy
+
+# Reset configuration
+ctdb_restart_when_done
+
+select_test_node_and_ips
+
+test_port=2049
+
+echo "Connecting to node ${test_node} on IP ${test_ip}:${test_port} with netcat..."
+
+nc -d -w 30 $test_ip $test_port &
+nc_pid=$!
+ctdb_test_exit_hook_add "kill $nc_pid >/dev/null 2>&1"
+
+wait_until_get_src_socket "tcp" "${test_ip}:${test_port}" $nc_pid "nc"
+src_socket="$out"
+echo "Source socket is $src_socket"
+
+echo "Getting MAC address associated with ${test_ip}..."
+releasing_mac=$(ip neigh show $test_prefix | awk '$4 == "lladdr" {print $5}')
+[ -n "$releasing_mac" ] || die "Couldn't get MAC address for ${test_prefix}"
+echo "MAC address is: ${releasing_mac}"
+
+tcptickle_sniff_start $src_socket "${test_ip}:${test_port}"
+
+echo "Disabling node $test_node"
+try_command_on_node 1 $CTDB disable -n $test_node
+wait_until_node_has_status $test_node disabled
+
+# Only look for a reset from the releasing node
+tcptickle_sniff_wait_show "$releasing_mac"