hydra

Class NetworkHelper

java.lang.Object

hydra.NetworkHelper

public class NetworkHelper
extends Object

Supports configuring network traffic between hosts. All methods involve synchronous remote calls and do not return until the network configuration is complete. Methods are synchronized in the hydra master so that all network configuration requests are processed sequentially.

It is illegal to stop network traffic to or from the master host. Tests using this API must therefore use at least three hosts, including the master host.

Hosts for which network traffic will be configured must be reserved for exclusive use. It is the responsibility of the user to ensure that all connections have been restored when the reservation is complete. The script netclean.sh generated in the test result directory can be used for this. It is invoked automatically by batterytest after the test completes, regardless of the test outcome.

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	CLEAR
protected static int	DROP
protected static int	RESTORE
protected static int	SHOW

Constructor Summary

Constructors

Constructor and Description
NetworkHelper()

Method Summary

Modifier and Type	Method and Description
protected static void	configure(String source, String target, int op, int way) Runs on master, using ProcessMgr to execute the command on the source.
static void	dropConnectionOneWay(String source, String target) Simulates a one-way dropped connection by stopping all network packets from the source host to the target host.
static void	dropConnectionTwoWay(String source, String target) Simulates a two-way dropped connection by stopping all network packets between the source host and the target host.
static Map	getConnectionState() Returns the current state of network connections, as viewed by hydra, mapping each source to its list of dropped targets.
protected static Map	getState() Runs on master.
static void	printConnectionState() Prints the current state of network connections, as viewed by hydra.
static void	restoreConnectionOneWay(String source, String target) Restores a previously dropped one-way connection by allowing all network packets from the source host to the target host.
static void	restoreConnectionTwoWay(String source, String target) Restores a previously dropped two-way connection by allowing all network packets between the source host and the target host.
static void	showConnectionState() Shows the current state of network connections, as viewed by iptables, for each host used in the test.
protected static void	showState() Runs on master.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DROP

protected static final int DROP

See Also:

Constant Field Values

RESTORE

protected static final int RESTORE

See Also:

Constant Field Values

CLEAR

protected static final int CLEAR

See Also:

Constant Field Values

SHOW

protected static final int SHOW

See Also:

Constant Field Values

Constructor Detail

NetworkHelper

public NetworkHelper()

Method Detail

dropConnectionOneWay

public static void dropConnectionOneWay(String source,
                                        String target)

Simulates a one-way dropped connection by stopping all network packets from the source host to the target host. Packets are stopped at the source NIC.

Throws:

HydraRuntimeException - if the required network control script is not available on the source host or there is an RMI exception.

IllegalArgumentException - if an argument is null, or the master host, or not in use by this test, or if the source and target are equal.

IllegalStateException - if any part of the network is already in the desired state.

dropConnectionTwoWay

public static void dropConnectionTwoWay(String source,
                                        String target)

Simulates a two-way dropped connection by stopping all network packets between the source host and the target host. Outgoing packets between the two hosts are stopped on the local NICs.

This is equivalent to invoking two mirror-image one-way calls, except that the two-way call will drop both directions under synchronization. It is possible for one direction to succeed and the other fail, resulting in an exception.

Throws:

HydraRuntimeException - if the required network control script is not available on the source host or there is an RMI exception.

IllegalArgumentException - if an argument is null, or the master host, or not in use by this test, or if the source and target are equal.

IllegalStateException - if any part of the network is already in the desired state.

restoreConnectionOneWay

public static void restoreConnectionOneWay(String source,
                                           String target)

Restores a previously dropped one-way connection by allowing all network packets from the source host to the target host.

Throws:

HydraRuntimeException - if the required network control script is not available on the source host or there is an RMI exception.

IllegalArgumentException - if an argument is null, or the master host, or not in use by this test, or if the source and target are equal.

IllegalStateException - if any part of the network is already in the desired state.

restoreConnectionTwoWay

public static void restoreConnectionTwoWay(String source,
                                           String target)

Restores a previously dropped two-way connection by allowing all network packets between the source host and the target host.

This is equivalent to invoking two mirror-image one-way calls, except that the two-way call will restore both directions under synchronization. It is possible for one direction to succeed and the other fail, resulting in an exception.

Throws:

HydraRuntimeException - if the required network control script is not available on the source host or there is an RMI exception.

IllegalArgumentException - if an argument is null, or the master host, or not in use by this test, or if the source and target are equal.

IllegalStateException - if any part of the network is already in the desired state.

getConnectionState

public static Map getConnectionState()

Returns the current state of network connections, as viewed by hydra, mapping each source to its list of dropped targets.

Throws:

HydraRuntimeException - if there is an RMI exception.

printConnectionState

public static void printConnectionState()

Prints the current state of network connections, as viewed by hydra.

showConnectionState

public static void showConnectionState()

Shows the current state of network connections, as viewed by iptables, for each host used in the test.

Throws:

HydraRuntimeException - if there is an RMI exception.

configure

protected static void configure(String source,
                                String target,
                                int op,
                                int way)

Runs on master, using ProcessMgr to execute the command on the source.

getState

protected static Map getState()

Runs on master.

showState

protected static void showState()

Runs on master.