Enabling and Disabling the Global Optimization Features
The global optimization features determine if TFO Optimization, Data Redundancy Elimination (DRE), and Persistent Compression are enabled on a device or device group. By default, all of these features are enabled. If you choose to disable one of these features, the device will be unable to apply the full WAAS optimization techniques to the traffic that it intercepts.
In addition, the global optimization features include each of the following application accelerators: EPM, CIFS, HTTP MAPI, NFS, and video. By default, all of the application accelerators are enabled. The application accelerators also require specific licenses to operate. For information on installing licenses, see the “Managing Software Licenses” section.
You must enable the accelerator on both of the peer WAEs at either end of a WAN link for all application accelerators to operate.
To enable or disable a global optimization feature, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices (
or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the device or device group for which you want to change the global optimization features.
Step 3 From the navigation pane, choose
Configure > Acceleration > Enabled Features
.
The Enabled Features window appears. (See Figure 12-1.)
Figure 12-1 Modifying the Global Optimization Features
Step 4 Place a check next to the optimization features that you want to enable, and uncheck the features that you want to disable. For a description of each of the optimization features, see the “Key Services of Cisco WAAS” section.
Step 5 If you check the Video Accelerator check box, you can click the More Settings link as a shortcut to the Video Acceleration Configuration window. For more information, see the “Configuring Video Acceleration” section.
Step 6 If you check the CIFS Accelerator check box, you have the following option:
– Windows Print Accelerator—Check this box to accelerate print traffic between clients and a Windows print server. This accelerator is enabled by default when you enable the CIFS accelerator.
Note If you are changing from WAFS legacy mode to the CIFS accelerator, you must disable the WAFS legacy mode before you can enable the CIFS accelerator. To disable WAFS legacy mode, you must disable Core and Edge file services. For WAFS configuration information, see Chapter11, “Configuring Wide Area File Services”
Note Do not disable Windows Print Acceleration during a client session as this can interfere with the client's use of print services. If you must disable Windows Print Acceleration, disconnect and then reestablish the client session.
Step 7 In the Advanced Settings area, uncheck the Blacklist Operation feature if you want to disable it. This feature allows a WAE to better handle situations in which TCP setup packets that have options are blocked or not returned to the WAE device. This behavior can result from network devices (such as firewalls) that block TCP setup packets that have options, and from asymmetric routes. The WAE can keep track of origin servers (such as those behind firewalls) that cannot receive optioned TCP packets and learns not to send out TCP packets with options to these blacklisted servers. WAAS is still able to accelerate traffic between branch and data center WAEs in situations where optioned TCP packets are dropped. We recommend leaving this feature enabled.
Step 8 If you want to change the default Blacklist Server Address Hold Time of 60 minutes, enter the new time in minutes in the Blacklist Server Address Hold Time field. The valid range is 1 minute to 10080 minutes (1 week).
When a server IP address is added to the blacklist, it remains there for configured hold time. After that time, subsequent connection attempts will again include TCP options so that the WAE can redetermine if the server can receive them. It is useful to retry sending TCP options periodically because network packet loss may cause a server to be erroneously blacklisted.
You can shorten or lengthen the blacklist time by changing the Blacklist Server Address Hold Time field.
Step 9 Click
Submit
.
The changes are saved to the device or device group.
To configure TFO optimization, DRE, and persistent compression from the CLI, use the
tfo optimize
global configuration command.
To configure EPM acceleration from the CLI, use the
accelerator epm
global configuration command.
To configure HTTP acceleration from the CLI, use the
accelerator http
global configuration command.
To configure NFS acceleration from the CLI, use the
accelerator nfs
global configuration command.
To configure MAPI acceleration from the CLI, use the
accelerator mapi
global configuration command.
To configure video acceleration from the CLI, use the
accelerator video
global configuration command.
To configure CIFS acceleration from the CLI, use the
accelerator cifs
and
accelerator cifs preposition
global configuration commands.
To configure Windows print acceleration from the CLI, use the
accelerator windows-print
global configuration command.
To configure the Blacklist Operation feature from the CLI, use the
tfo auto-discovery
global configuration command.
To display status and statistics on the application accelerators from the CLI, use the
show accelerator
and
show statistics accelerator
EXEC commands. To display statistics on the Windows print accelerator, use the
show statistics windows-print requests
EXEC command.
For details on using individual application accelerators, see the following sections:
Configuring HTTP Acceleration
The HTTP application accelerator accelerates HTTP traffic.
The default Web application policy is defined to send traffic to the HTTP accelerator. The Web application policy uses the HTTP classifier, which matches traffic on ports 80, 8080, 8000, 8001, and 3128. If you expect HTTP traffic on other ports, add the other ports to the HTTP classifier.
Configuring MAPI Acceleration
The MAPI application accelerator accelerates Microsoft Outlook Exchange traffic that uses the Messaging Application Programming Interface (MAPI) protocol. Microsoft Outlook 2000–2007 clients are supported. Clients can be configured with Outlook in cached or noncached mode; both modes are accelerated.
Secure connections that use message authentication (signing) or encryption are not accelerated, and MAPI over HTTP is not accelerated.
Note Microsoft Outlook 2007 has encryption enabled by default. You must disable encryption to benefit from the MAPI application accelerator.
The EPM application accelerator must be enabled for the MAPI application accelerator to operate. EPM is enabled by default. Additionally, the system must define an application policy of type EPM, specify the MAPI UUID, and have an Accelerate setting of MAPI. This policy, MAPI for the Email-and-Messaging application, is defined by default.
EPM traffic, such as MAPI, does not normally use a predefined port. If your Outlook administrator has configured Outlook in a nonstandard way to use a static port, you must create a new basic application policy that accelerates MAPI traffic with a classifier that matches the static port that was configured for Outlook.
Note The MAPI application accelerator is not supported on a branch WAE device with the Cisco WAE Inline Network Adapter, where multiple inline devices are deployed in series. All MAPI connections must go through the same WAE. Outlook clients may receive errors in this case.
Configuring Video Acceleration
The video application accelerator accelerates Windows Media live video broadcasts that use RTSP over TCP. The video accelerator automatically splits one source video stream from the WAN into multiple streams to serve multiple clients on the LAN.
The video accelerator automatically causes the client that is requesting a UDP stream to do a protocol rollover to use TCP (if both the client and server allow TCP).
The default RTSP classifier for the Streaming application policy is defined to send traffic to the video accelerator.
By default, the video accelerator sends any unaccelerated video traffic to be handled by the configured standard TCP optimization policy unless the video accelerator is explicitly configured to drop such traffic.
To enable the video accelerator, check the Video Accelerator check box in the Enabled Features window (see Figure 12-1).
To configure the video acceleration settings, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices (
or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the device or device group for which you want to change the video acceleration configuration.
Step 3 From the navigation pane, choose
Configure > Acceleration > Video Acceleration Advanced Settings
.
The Video Acceleration Configuration window appears. (See Figure 12-2.)
Figure 12-2 Modifying the Video Acceleration Configuration
Step 4 In the Un-accelerated video traffic handling field, choose how to handle video traffic that is not being accelerated due to unsupported transport or format, or overload. Choose
TCP Optimize
(the default) to handle such connections with the configured TCP optimization policy, or choose
Drop
to drop the traffic. If you choose Drop, all Windows Media video-on-demand traffic and all non-Windows Media RTSP traffic is dropped.
Step 5 In the Maximum Initial Setup Delay field, enter the number of seconds to wait for the first message from the client and the first response from the server, after the connection is accepted by the video accelerator, before timing out the connection. Valid values range from 10–180 seconds. The default is 60.
Step 6 Check the
Enable transaction logs
check box to enable transaction logging. This feature will generate a large amount of logging data. This box is unchecked by default.
Step 7 Check the
Enable log forwarding
check box to enable forwarding of Windows Media logs to the upstream Windows Media Server. This box is checked by default.
Step 8 In the Client Idle Connection timeout field, enter the maximum number of seconds to wait after the initial client request, while the client connection is idle, before timing out the connection. Valid values range from 30–300 seconds. The default is 60.
Step 9 Click
Submit
.
The changes are saved to the device or device group.
Creating a New Traffic Application Policy
Table 12-1
provides an overview of the steps that you must complete to create a new traffic application policy.
Table 12-1 Checklist for Creating a New Application Policy
|
Additional Information and Instructions
|
Prepare for creating an application policy.
|
Provides the tasks you need to complete before creating a new application policy on your WAAS devices. For more information, see the “Preparing to Create an Application Policy” section.
|
Create an application definition.
|
Identifies general information about the application you want to optimize, such as the application name and whether the WAAS Central Manager collects statistics about this application. This step also allows you to assign the application definition to a device or device group. For more information, see the “Creating an Application Definition” section.
|
Create an application policy.
|
Determines the type of action your WAAS device or device group performs on specific application traffic. This step requires you to do the following:
-
Create application classifiers that allow a WAAS device to identify specific types of traffic. For example, you can create a condition that matches all traffic going to a specific IP address.
-
Specify the type of action your WAAS device or device group performs on the defined traffic. For example, you can specify that WAAS should apply TFO and LZ compression to all traffic for a specific application.
For more information, see the “Creating an Application Policy” section.
|
Preparing to Create an Application Policy
Before you create a new application policy, complete the following preparation tasks:
-
Review the list of application policies on your WAAS system and make sure that none of these policies already cover the type of traffic you want to define. To view a list of the default policies that come bundled with the WAAS system, see
Appendix A, “Default Application Policies.”
-
Identify a match condition for the new application traffic. For example, if the application uses a specific destination or source port, you can use that port number to create a match condition. You can also use a source or destination IP address for a match condition.
-
Identify the device or device group that requires the new application policy. We recommend you create application policies on device groups so the policy is consistent across multiple WAAS devices.
Creating an Application Definition
The first step in creating an application policy is to set up an application definition that identifies general information about the application, such as the application name and whether you want the WAAS Central Manager to collect statistics about the application. After creating the application definition, you assign it to a device or device group. You can create up to 255 application definitions on your WAAS system.
To create an application definition, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
Configure > Acceleration > Applications
.
The Applications window appears, which displays a list of all applications on your WAAS system. From this window, you can perform the following tasks:
-
Click the
Edit
icon next to an application to modify or delete the definition.
-
Determine if your WAAS system is collecting statistics on an application. The Monitor Enabled column displays Yes if statistics are being collected for the application.
-
Create a new application as described in the steps that follow.
Click the
Create New Application
icon in the taskbar. The Creating Application window appears. (See Figure 12-3.)
Figure 12-3 Creating a New Application
Step 2 Enter a name for this application.
The name cannot contain spaces and special characters.
Step 3 Check the
Enable Statistics
check box to allow the WAAS Central Manager to collect data for this application. To disable data collection for this application, uncheck this box.
The WAAS Central Manager GUI can display statistics for up to 20 applications, and an error message is displayed if you try to enable statistics for the twenty-first application. However, you can use the WAAS CLI to view statistics for all applications that have policies on a specific WAAS device. For more information, refer to the
Cisco Wide Area Application Services Command Reference
.
If you are collecting statistics for an application and decide to disable statistics collection, then reenable statistics collection at a later time, the historical data will be retained, but a gap in data will exist for the time period when statistics collection was disabled. However, if you delete an application that you are collecting statistics for, then later recreate the application, the historical data for the application will be lost. Only data since the recreation of the application will be displayed.
Note The WAAS Central Manager does not start collecting data for this application until you finish creating the entire application policy.
Step 4 (Optional) Enter a comment in the
Comments
field.
The comment you enter appears in the Applications window shown in Figure 12-3.
Step 5 Click
Submit
.
The application definition is saved, and options appear in the navigation pane that allow you to assign the application to a device or device group.
Step 6 From the navigation pane, click one of the following options:
-
Assign Device Groups
—Assigns the application to one or more device groups.
-
Assign Devices
—Assigns the application to one or more WAAS devices.
The Device Groups Assignments window or the WAE Assignments window appears depending on the selected option.
Step 7 Choose the devices or device groups that you want to assign to this application. To select the devices, use one of the following procedures:
in the taskbar to assign all available WAAS devices or device groups.
next to each WAAS device or device group that you want to assign. The icon changes to
when selected. To unassign a device or device group, click the icon again.
Step 8 Click
Submit
.
The icon next to the selected devices changes to
, showing that the application has been successfully assigned to the devices.
Creating an Application Policy
After you create an application definition, you need to create an application policy that determines the action a WAAS device takes on the specified traffic. For example, you can create an application policy that makes a WAAS device apply TCP optimization and compression to all application traffic that travels over a specific port or to a specific IP address. You can create up to 512 application policies on your WAAS system.
The traffic matching rules are contained in the application classifier. These rules, known as match conditions, use Layer 2 and Layer 4 information in the TCP header to identify traffic.
To create an application policy, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices
(
or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the device or device group on which you want to create an application policy.
The Device Dashboard window or the Modifying Device Group window appears.
Step 3 From the navigation pane, choose
Configure > Acceleration > Policy Definitions
.
The Application Policies window appears. (See Figure 12-4.)
Figure 12-4 Application Policies Window
This window displays information about all the application policies that reside on the selected device or device group. The last column shows the type of policy (Basic, WAFS transport, Port Mapper, or Other) and the position of the policy within that type. The position determines the order in which WAAS refers to that policy when determining how to handle application traffic. To change the position of a policy, see the “Modifying the Position of an Application Policy” section. This window also displays the classifier, application definition, and action assigned to each policy.
From the Application Policies window, you can perform the following tasks:
-
Click the
Edit
icon next to an application policy to modify or delete that policy.
-
Restore default policies and classifiers. For more information, see the “Restoring Application Policies and Classifiers” section.
-
Create a new application policy as described in the steps that follow.
Step 4 Click the
Create New Policy
icon in the taskbar to create a new application policy.
The Creating New Application Policy window appears. (See Figure 12-5.)
Figure 12-5 Creating a New Application Policy
Step 5 From the Type drop-down list, choose the type of application policy.
Table 12-2
describes the types of application policies.
Table 12-2 Application Policy Types
|
|
Basic
|
Standard type of application policy. Choose this option if none of the other types apply.
|
WAFS Transport
|
When you enable wide area file services (WAFS), all CIFS traffic going between a branch WAE and a data center WAE is optimized. Choose the
WAFS Transport
option to specify another action (such as passthrough) for CIFS traffic traveling between branch and data center WAEs.
For more information on enabling file services, see Chapter11, “Configuring Wide Area File Services”
|
EPM
|
Type of policy for EPM-based applications. EndPoint Mapper (EPM) is a service that dynamically allocates server ports to certain applications. Unlike most applications that always use the same port, applications that rely on the EPM service can be assigned a different port at every request.
Because EPM applications do not use a static port, you must specify the application’s UUID as a way to identify the application traffic to your WAAS system.
When you select the EPM option, the UUID field is enabled so that you can select a preconfigured EPM application or enter the UUID for a custom application.
|
Step 6 If you chose EPM for the policy type, choose one of the following EPM applications from the
UUID
drop-down list:
-
MAPI
—Uses the predefined UUID associated with the MAPI application, which is a4f1db00-ca47-1067-b31f-00dd010662da.
-
MS-SQL-RPC
—Uses the predefined UUID associated with the SQL Session Manager application, which is 3f99b900-4d87-101b-99b7-aa0004007f07.
-
MS-AD-Replication
—Uses the predefined UUID associated with the Active Directory application, which is e3514235-4b06-11d1-ab04-00c04fc2dcd2.
-
MS-FRS
—Uses the predefined UUID associated with the file replication service, which is f5cc59b4-4264-101a-8c59-08002b2f8426.
-
Custom
—Allows you to enter the UUID for a custom EPM application in the Custom UUID field.
Step 7 Specify the application that you want to be associated with this policy by doing either of the following:
-
From the Application drop-down list, choose an existing application like the one that you created in the “Creating an Application Definition” section. This list displays all default and new applications on your WAAS system.
To modify an existing application, choose the application from the drop-down list and click
Edit Application
. You can then change the application’s name, add or remove comments, and enable or disable statistics collection for the application. After making the necessary changes, click
Submit
to save your changes and return to the Application Policy window.
-
Click
New Application
to create a new application. You can specify the application name, enable statistics collection, and specify the DSCP marking value. For the DSCP marking, you can choose to use the global default values (see the “Defining Default DSCP Marking Values” section) or select one of the other defined values. See Table 11-4 for a description of the supported DSCP marking values. In addition to the values listed in
Table 11-4
, you can choose copy, which copies the DSCP value from the incoming packet and uses it for the outgoing packet. After specifying the application details, click
Submit
to save the new application and return to the Application Policy window. The new application is automatically assigned to this device or device group.
Step 8 Choose the classifier from the Application Classifier drop-down list to select an existing classifier for this policy.
To modify an existing classifier, select the classifier from the drop-down list and click
Edit Classifier
. You can then change classifier’s name, add or remove comments, create a new match condition, or edit the existing match condition. After making the necessary changes, click
Submit
to save your changes and return to the Application Policy window.
Step 9 Click
New Classifier
to create a new classifier for this policy.
The Creating New Application Classifier window then appears so that you can create a new classifier. Complete the following steps to create a new classifier:
a. Enter a name for this application classifier. The name cannot contain spaces or special characters.
b. (Optional) Enter a comment that will appear on the Application Policies window shown in Figure 12-4.
c. In the Configure Match Conditions section, click the
Create New Match Condition
icon. (If you get a dialog box asking if you want to navigate away from the page, click
OK
.) The Creating New Match Condition window appears. (See Figure 12-6.)
Figure 12-6 Creating a New Match Condition
d. Check the
Match All
check box to create a condition that matches all traffic. Checking the Match All
check box automatically disables all other fields in the window.
e. Enter a value in one of the destination or source condition fields to create a condition for a specific type of traffic.
For example, to match all traffic going to IP address 10.10.10.2, enter that IP address in the Destination IP Address field.
Note To specify a range of IP addresses, enter a wildcard subnet mask in either the destination or source IP Wildcard field.
f. Click
Update Classifier
. You return to the Creating New Application Classifier window. The new match condition appears at the bottom of this window.
g. Click
Submit
. You return to the Creating New Application Policy window.
Step 10 From the Action drop-down list, choose the action that your WAAS device should take on the defined traffic.
Table 12-3
describes each action.
Table 12-3 Action Descriptions
|
|
Passthrough
|
Prevents the WAAS device from optimizing the application traffic defined in this policy by using TFO, DRE, or compression. Traffic that matches this policy can still be accelerated if an accelerator is chosen from the Accelerate drop-down list.
|
TFO Only
|
Applies a variety of transport flow optimization (TFO) techniques to matching traffic. TFO techniques include BIC-TCP, window size maximization and scaling, and selective acknowledgement. For a more detailed description of the TFO features, see the “TFO Optimization” section.
|
TFO with Data Redundancy Elimination
|
Applies both TFO and data redundancy elimination (DRE) to matching traffic. DRE removes redundant information before sending the shortened data stream over the WAN. DRE operates on large data streams (tens to hundreds of bytes or more).
|
TFO with LZ Compression
|
Applies both TFO and the LZ compression algorithm to matching traffic. LZ compression functions similarly to DRE but uses a different compression algorithm to compress smaller data streams and maintains a limited compression history.
|
Full Optimization
|
Applies TFO, DRE, and LZ compression to matching traffic.
|
Step 11 From the Accelerate drop-down list, choose one of the following additional acceleration actions that your WAAS device should take on the defined traffic:
-
Do Not Set
—No additional acceleration is done.
-
MS Port Mapper
—Accelerate using the Microsoft Endpoint Port Mapper (EPM).
-
CIFS
—Accelerate using the CIFS Accelerator.
-
HTTP
—Accelerate using the HTTP Accelerator.
-
NFS
—Accelerate using the NFS Accelerator.
-
MAPI
—Accelerate using the MAPI Accelerator.
-
VIDEO
—Accelerate using the Video Accelerator.
Step 12 Choose one of the following positions for this application policy by click the appropriate Position radio button:
-
First
—Places this policy at the top of the position list so that the WAAS device tries to classify traffic using this policy before moving onto the second policy in the list. If you already have a policy in the first position, that policy moves down to number two in the list.
-
Last
—Places this policy at the bottom of the position list, making it the last policy that the WAAS device uses to classify traffic. If you already have a policy in the last position, that policy becomes the second to last in the list.
If a device goes through all the policies in the list without making a match, then the WAAS device passes through the traffic unoptimized.
-
Specific
—Allows you to enter a specific position for this policy. If you already have a policy in the specified position, that policy moves down one in the list.
Step 13 (Optional) Select a value from the DSCP Marking drop-down list and see Table 11-4 for a description of the supported values. In addition to the values listed in
Table 11-4
, you can choose copy, which copies the DSCP value from the incoming packet and uses it for the outgoing packet. If you choose inherit-from-name from the drop-down list, the DSCP value defined at the application or global level is used.
DSCP is a field in an IP packet that enables different levels of service to be assigned to network traffic. Levels of service are assigned by marking each packet on the network with a DSCP code and associating a corresponding level of service. DSCP is the combination of IP Precedence and Type of Service (ToS) fields. For more information, see RFC 2474.
DSCP marking does not apply to pass-through traffic.
The DSCP value set at the application level applies to all classifiers associated with the application. If you set a DSCP value in a policy, it overrides the DSCP value set at the application or global level.
Step 14 Check the
Enabled
check box to activate this policy. To disable this policy, uncheck this box.
Step 15 Click
Submit
.
The new policy appears in the Application Policies window. (See Figure 12-4.)
Managing Application Acceleration
This section contains the following topics:
Viewing a List of Applications
To view a list of applications that reside on a WAE device or device group, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices
(
or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the device or device group on which you want to view applications.
Step 3 From the navigation pane, choose
Configure > Acceleration > Policy Definitions
. The Application Policies window appears.
Step 4 Click the Application column header to sort the column by application name so you can more easily locate a specific application.
Viewing a Policy Report
To view a report of the policies that reside on each WAE device or device group, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
Configure > Acceleration > Policies
.
The policy report appears. It lists each device or device group and the number of active policies on the device or device group.
Step 2 Click the
Edit
icon next to a device or group to see the application policies that are defined on it.
Viewing a Classifier Report
To view a report of the classifiers that reside on each WAE device or device group, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
Configure > Acceleration > Classifiers
.
The classifier report appears. It lists each classifier that is defined, and the number of devices on which it is configured.
Step 2 Click the
View
icon next to a classifier to see a report of the devices and device groups on which the classifier is configured.
Step 3 Click the
Edit
icon next to a device or group to see the application policies that are defined on it.
Restoring Application Policies and Classifiers
The WAAS system allows you to restore the default policies and classifiers that shipped with the WAAS system. For a list of the default policies, see
Appendix A, “Default Application Policies.”
If you made changes to the default policies that have negatively impacted how a WAAS device handles application traffic, you can override your changes by restoring the default policy settings.
To restore default policies and classifiers, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices
(
or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the device or group on which you want to restore policies.
Step 3 From the navigation pane, choose
Configure > Acceleration > Policy Definitions
.
The Application Policies window appears.
Step 4 Click the
Restore Default Policies and Classifiers
taskbar icon to restore over 150 policies and classifiers that shipped with the WAAS software and remove any new policies that were created on the system. If a default policy has been changed, these changes are lost and the original settings are restored.
Monitoring Applications
After you create an application policy, you should monitor the associated application to make sure your WAAS system is handling the application traffic as expected. To monitor an application, you must have enabled statistics collection for that application, as described in the “Creating an Application Definition” section.
You can use the Network Traffic Application Mix report to monitor a specific application. For more information, see the “Using Predefined Reports to Monitor WAAS” section.
Defining Default DSCP Marking Values
According to policies that you define in an application definition and an application policy, the WAAS software allows you to set a DSCP value on packets that it processes.
A DSCP value is a field in an IP packet that enables different levels of service to be assigned to the network traffic. The levels of service are assigned by marking each packet on the network with a DSCP code and associating a corresponding level of service. The DSCP marking determines how packets for a connection are processed externally to WAAS. DSCP is the combination of IP Precedence and Type of Service (ToS) fields. For more information, see RFC 2474. DSCP values are predefined and cannot be changed.
This attribute can be defined at the following levels:
-
Global—You can define global defaults for the DSCP value. This value applies to the traffic if a lower level value is not defined.
-
Application—You can define the DSCP value in an application definition at the device or device group level but not at the global application definition level. This value applies to all traffic associated with the application on a particular device or device group and overrides the global default.
-
Policy—You can define the DSCP value in an application policy. This value applies only to traffic that matches the classifiers defined in the policy and overrides the application or global DSCP value.
This section contains the following topic:
Defining the Default DSCP Marking Value
To define the global default DSCP marking value, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices (
or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the device or group where you want to define the default DSCP marking value.
Step 3 From the navigation pane, choose
Configure > Acceleration > DSCP Marking
. The Global DSCP Settings window appears.
Step 4 Choose a value from the Global Default DSCP Marking drop-down list and see Table 11-4 for a description of the supported values. In addition to the values listed in
Table 11-4
, the default setting is copy, which copies the DSCP value from the incoming packet and uses it for the outgoing packet.
Step 5 Click
Submit
to save the settings.
Modifying the Position of an Application Policy
Each application policy has an assigned position that determines the order in which a WAAS device refers to the policy in an attempt to classify traffic. For example, when a WAAS device intercepts traffic, it refers to the first policy in the list to try to match the traffic to an application. If the first policy does not provide a match, the WAAS device moves on to the next policy in the list.
For information on how to assign a position to a new policy, see the “Creating an Application Policy” section.
You should consider the position of policies that pass through traffic unoptimized because placing these policies at the top of the list can cancel out optimization policies that appear farther down the list. For example, if you have two application policies that match traffic going to IP address 10.10.10.2, and one policy optimizes this traffic and a second policy in a higher position passes through this traffic, then all traffic going to 10.10.10.2 will go through the WAAS system unoptimized. For this reason, you should make sure that your policies do not have overlapping matching conditions, and you should monitor the applications you create to make sure that WAAS is handling the traffic as expected. For more information on monitoring applications, see Chapter16, “Monitoring and Troubleshooting Your WAAS Network”
To modify the position of an application policy, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices (
or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the device or group that contains the application policy to modify.
Step 3 From the navigation pane, choose
Configure > Acceleration > Policy Prioritization
.
Step 4 The Application Policies window appears. This window categorizes policies into these categories: Basic, Other, Port Mapper, and WAFS.
Step 5 Click the arrow next to the appropriate category to display the list of applications for that category. (See Figure 12-7.)
In most cases, the application you want to change the position for will be located under the Basic Policies category because that category contains a majority of the default applications that shipped with the WAAS system. For a list of these default policies, see
Appendix A, “Default Application Policies.”
Figure 12-7 Modifying the Position of Application Policies
Step 6 Click the arrow next to the policy category to view the list of applications for that category.
Step 7 Use the up and down arrows (
) next to a policy to move that policy higher or lower in the list.
Step 8 If you determine that a policy is not needed, follow these steps to delete the policy:
a. Click the
Edit
icon next to the policy you want to delete.
The Modifying Application Policy window appears.
b. Click the
Delete
icon in the taskbar.
Modifying the Acceleration TCP Settings
In most cases, you do not need to modify the acceleration TCP settings because your WAAS system automatically configures the acceleration TCP settings based on the hardware platform of the WAE device. WAAS automatically configures the settings only under the following circumstances:
-
When you first install the WAE device in your network.
-
When you enter the
restore factory-default
command on the device. For more information about this command, see the
Cisco Wide Area Application Services Command Reference
.
The WAAS system automatically adjusts the maximum segment size (MSS) to match the advertised MSS of the client or server for each connection. The WAAS system uses the lower of 1432 or the MSS value advertised by the client or server.
If your network has high BDP links, you may need to adjust the default buffer settings automatically configured for your WAE device. For more information, see the “Calculating the TCP Buffers for High BDP Links” section.
If you want to adjust the default TCP adaptive buffering settings for your WAE device, see the “Modifying the TCP Adaptive Buffering Settings” section.
To modify the acceleration TCP settings, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices
(
or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the device or device group for which you want to change the acceleration TCP settings.
Step 3 From the navigation pane, choose
Configure > Acceleration > TCP Settings
. The Acceleration TCP Settings window appears.
Step 4 Keep the
Send TCP Keepalive
check box checked.
Note Enabling TCP keepalives between the branch and data center WAEs impacts the WAAS system’s ability to accommodate network disruptions.
Checking the Send TCP Keepalive check box allows this WAE device or group to disconnect the TCP connection to its peer device if no response is received from the TCP keepalive exchange. In this case, the two peer WAE devices will exchange TCP keepalives on a TCP connection and if no response is received for the keepalives for a specific period, the TCP connection will be torn down. When the keepalive option is enabled, any short network disruption in the WAN will cause the TCP connection between peer WAE devices to be disconnected.
If the Send TCP Keepalive check box is not checked, TCP keepalives will not be sent and connections will be maintained unless they are explicitly disconnected. By default, this setting is enabled.
Step 5 Modify the TCP acceleration settings as needed. See
Table 12-4
for a description of these settings.
For information on how to calculate these settings for high BDP links, see the “Calculating the TCP Buffers for High BDP Links” section.
Table 12-4 TCP Settings
|
|
|
Maximum Segment Size
|
Maximum packet size allowed between this WAAS device and other WAAS devices participating in the optimized connection. The default is 1432 bytes.
|
Send Buffer Size
|
Allowed TCP sending buffer size (in kilobytes) for TCP packets sent from this WAAS device to other WAAS devices participating in the optimized connection. The default is 512 KB.
|
Receive Buffer Size
|
Allowed TCP receiving buffer size (in kilobytes) for incoming TCP packets from other WAAS devices participating in the optimized connection. The default is 512 KB.
|
|
Maximum Segment Size
|
Maximum packet size allowed between the origin client or server and this WAAS device. The default is 1432 bytes.
|
Send Buffer Size
|
Allowed TCP sending buffers size (in kilobytes) for TCP packets sent from this WAAS device to the origin client or server. The default is 32 KB.
|
Receive Buffer Size
|
Allowed TCP receiving buffer size (in kilobytes) for incoming TCP packets from the origin client or server. The default is 32 KB.
|
Step 6 If you are deploying the WAE across a high Bandwidth-Delay-Product (BDP) link, you can set recommended values for the send and receive buffer sizes by clicking the
Set High BDP recommended values
button. For more information about calculating TCP buffers for high BDP links, see the “Calculating the TCP Buffers for High BDP Links” section.
Step 7 Click
Submit
.
Calculating the TCP Buffers for High BDP Links
WAAS software can be deployed in different network environments, involving multiple link characteristics such as bandwidth, latency, and packet loss. All WAAS devices are configured to accommodate networks with maximum Bandwidth-Delay-Product (BDP) of up to the values listed below:
-
WAE-511/512—Default BDP is 32 KB
-
WAE-611/612—Default BDP is 512 KB
-
WAE-674 —Default BDP is 2048 KB
-
WAE-7326 —Default BDP is 2048 KB
-
WAE-7341 —Default BDP is 2048 KB
-
WAE-7371 —Default BDP is 2048 KB
-
WAVE-274 —Default BDP is 2048 KB
-
WAVE-474 —Default BDP is 2048 KB
-
WAVE-574—Default BDP is 2048 KB
If your network provides higher bandwidth or higher latencies are involved, use the following formula to calculate the actual link BDP:
BDP [Kbytes] = (link BW [Kbytes/sec] * Round-trip latency [Sec])
When multiple links 1..N are the links for which the WAE is optimizing traffic, the maximum BDP should be calculated as follows:
MaxBDP = Max (BDP(link 1),..,BDP(link N))
If the calculated MaxBDP is greater than the DefaultBDP for your WAE model, the Acceleration TCP settings should be modified to accommodate that calculated BDP.
Once you calculate the size of the Max BDP, enter that value in the Send Buffer Size and Receive Buffer Size for the optimized connection on the Acceleration TCP Settings window.
Note These manually configured buffer sizes apply only if TCP adaptive buffering is disabled. TCP adaptive buffering is normally enabled, and allows the WAAS system to dynamically vary the buffer sizes. For more information on TCP adaptive buffering, see the “Modifying the TCP Adaptive Buffering Settings” section.
Modifying the TCP Adaptive Buffering Settings
In most cases, you do not need to modify the acceleration TCP adaptive buffering settings because your WAAS system automatically configures the TCP adaptive buffering settings based on the network bandwidth and delay experienced by each connection. Adaptive buffering allows the WAAS software to dynamically vary the size of the send and receive buffers to increase performance and more efficiently use the available network bandwidth.
To modify the acceleration TCP adaptive buffering settings, follow these steps:
Step 1 From the WAAS Central Manager GUI navigation pane, choose
My WAN > Manage Devices
(or
Manage Device Groups
).
Step 2 Click the
Edit
icon next to the name of the device (or device group) for which you want to configure the TCP adaptive buffering settings.
Step 3 In the navigation pane, choose
Configure > Acceleration > TCP Adaptive Buffering Settings
. The TCP Adaptive Buffering Settings window appears.
Step 4 To enable TCP adaptive buffering, check the
Enable
check box. The default is enabled.
Step 5 In the Send Buffer Size and Receive Buffer Size fields, enter the maximum size in kilobytes of the send and receive buffers.
Step 6 Click
Submit
.
To configure the TCP adaptive buffer settings from the CLI, use the
tfo tcp adaptive-buffer-sizing
global configuration command:
WAE(config)# tfo tcp adaptive-buffer-sizing receive-buffer-max 8192
To disable TCP adaptive buffering from the CLI, use the
no tfo tcp adaptive-buffer-sizing enable
global configuration command.
To show the default and configured adaptive buffer sizes, use the
show tfo tcp
EXEC command.