-
Cisco Traffic Anomaly Detector Configuration Guide (Software Version 6.0)
-
Index
-
Preface
-
Product Overview
-
Initializing the Detector
-
Configuring the Detector
-
Configuring Zones
-
Configuring Zone Filters
-
Configuring Policy Templates and Policies
-
Learning the Zone Traffic Characteristics
-
Detecting Zone Traffic Anomalies
-
Using Interactive Detect Mode
-
Using Attack Reports
-
Using Detector Diagnostic Tools
-
Performing Maintenance Tasks
-
Feedback
Table Of Contents
Creating a New Zone from a Zone Template
Creating a New Zone by Duplicating an Existing Zone
Configuring the Zone IP Address Range
Synchronizing Zone Configurations with a Guard
Understanding the Configuration Guidelines for Synchronization
Creating a Zone for Synchronization
Configuring the Automatic Zone Synchronization and Export Parameters
Synchronizing a Zone Configuration from the Guard to the Detector
Synchronizing a Zone Configuration from the Detector to the Guard
Synchronizing a Zone Configuration Offline
Exporting a Zone Configuration Automatically to a Network Server
Exporting a Zone Configuration Manually to a Network Server
Example Synchronization Scenario
Configuring Zones
This chapter describes how to create and manage zones on the Cisco Traffic Anomaly Detector (Detector).
This chapter refers to the Cisco Guard (Guard), the companion product of the Detector. The Guard is a Distributed Denial of Service (DDoS) attack detection and mitigation device that cleans the zone traffic as the traffic flows through it, dropping the attack traffic and injecting the legitimate traffic back into the network. When the Detector determines that the zone is under attack, it can activate the Guard attack mitigation services. The Detector can also synchronize zone configurations with the Guard. For more information about the Guard, see the Cisco Anomaly Guard Module Configuration Guide or the Cisco Guard Configuration Guide.
This chapter contains the following sections:
•
Configuring the Zone IP Address Range
•
Understanding Zones
A zone is a network element that the Detector monitors for DDoS attacks. A zone can be any combination of the following elements:
•
•
•
•
When the Detector identifies a DDoS attack, it can activate a Guard automatically to protect the zone against the attack, or it can notify you to activate the Guard manually. The Detector can analyze the traffic for different zones simultaneously providing their network address ranges do not overlap.
The zone configuration process consists of the following tasks:
•
•
•
•
Using Zone Templates
A zone template defines the default configuration of a zone.
The Detector contains two sets of zone templates with the following prefixes:
•
•
See the "Creating a Zone for Synchronization" section for more information about how to configure zones that you create using GUARD_ templates.
Table 4-1 displays the zone templates.
Table 4-1 Zone Templates
DETECTOR_DEFAULT
Default Detector-only zone template. You can use this zone template to protect a VoIP1 server.
If you create a zone using this zone template, you cannot detect TCP worm attacks on the zone.
DETECTOR_WORM
Zone template that enables the Detector to detect TCP worm attacks on the zone. Zones that are created from the DETECTOR_WORM zone template contain policies that are produced from the worm_tcp policy template (see the "Understanding Worm Policies" section on page 6-19 for more information).
DETECTOR_LINK Templates
Zone templates designed for detection of large subnets segmented according to zones with known bandwidth. You can activate zone detection for zones defined by these zone templates without undergoing the learning process. To enable the Detector to activate zone protection on a Guard for the attacked IP address or subnet only, use the protect-ip-state dst-ip-by-name command. See the "Configuring Guard-Protection Activation Methods" section on page 8-3 for more information about the protect-ip-state command.
The following bandwidth-limited link zone templates are available for 128-Kb, 1-Mb, 4-Mb, and 512-Kb links:
DETECTOR_LINK_128K
DETECTOR_LINK_1M
DETECTOR_LINK_4M
DETECTOR_LINK_512K
You cannot perform the policy construction phase of the learning process for zones that were created from these templates.
GUARD_DEFAULT
Default zone template.
GUARD_LINK templates
Zone templates designed for zones with a known bandwidth. The following templates are available for 128-Kb, 1-Mb, 4-Mb, and 512-Kb links:
GUARD_LINK_128K
GUARD_LINK_1M
GUARD_LINK_4M
GUARD_LINK_512K
You cannot perform policy construction for zones that were created from these templates. You can activate zone detection for zones that were created from the GUARD_LINK zone templates without undergoing the threshold tuning phase.
We recommend that you define such a zone with a Guard protection activation method of dst-ip-by-name (the Detector activates a Guard to protect a particular IP address when it detects an anomaly in the zone traffic that is destined to that IP address) by using the protect-ip-state command. See the "Configuring Guard-Protection Activation Methods" section on page 8-3 for more information.
GUARD_
TCP_NO_PROXYZone template designed for a zone for which no TCP proxy is to be used. You may use this zone template if the zone is controlled based on IP addresses, such as an IRC2 server-type zone, or if you do not know the type of services running on the zone.
1 VoIP = Voice over IP
2 IRC = Internet Relay Chat
Creating a New Zone
You can create a zone and configure the zone name, description, network address, operation definitions, and networking definitions. When you create a new zone, you can use an existing zone as a template or you can create a zone using a system-defined zone template. The zone template that you use defines the initial policy and filter configurations of the zone.
The two ways that you can create a new zone are as follows:
•
After you create a new zone, you must configure the zone attributes.
•
See the "Configuring Zone Attributes" section for information about how to modify the zone configuration settings.
This section contains the following topics:
•
•
Creating a New Zone from a Zone Template
When you use a zone template to create a new zone, the zone template provides a set of predefined policies and policy thresholds for the new zone configuration.
To create a new zone using a predefined zone template, use the following command in configuration mode:
zone zone-name [template-name] [interactive]
Table 4-2 provides the arguments and keywords for the zone command.
Table 4-2 Arguments and Keywords for the zone Command
zone-name
Name of the zone. Enter one of the following zone name types:
•
•
template-name
(Optional) Zone template that defines the zone configuration. If you entered a new zone name and do not specify a zone template, the Detector creates the zone using the DETECTOR_DEFAULT template (see the "Using Zone Templates" section for more information about the zone templates).
If you enter the name of an existing zone without specifying a zone template, the Detector enters the zone configuration mode of the existing zone without making any changes to its configuration.
See Table 4-1 for a list of available zone templates.
interactive
(Optional) Configures the Detector to perform zone anomaly detection in the interactive detect mode. See Chapter 9, "Using Interactive Detect Mode," for more information.
When you enter the zone command, the Detector enters the configuration mode of the new zone.
The following example shows how to create a new zone configured for interactive detect mode:
user@DETECTOR-conf# zone scannet interactiveuser@DETECTOR-conf-zone-scannet#To delete a zone, use the no zone command. When deleting a zone, you can use an asterisk (*) as a wildcard character at the end of the zone name. The wildcard allows you to remove several zones with the same prefix in one command.
To display the zone templates, use the show templates command in global or configuration mode. To display the zone template default policies, use the show templates template-name policies command in global or configuration mode.
Creating a New Zone by Duplicating an Existing Zone
You can create a new zone by creating a copy of an existing zone. When using an existing zone as a template for the new zone, all properties of the source zone are copied to the new zone. If you specify a zone snapshot as the source zone, the zone policies are copied from the snapshot.
To create a copy of a zone, use one of the following commands:
•
•
Table 4-3 provides the arguments and keywords for the zone command.
Table 4-3 Arguments and Keywords for the zone Command
new-zone-name
Name of a new zone. The name is an alphanumeric string from 1 to 63 characters. The string must start with an alphabetic letter and can contain underscores but cannot contain any spaces.
copy-from-this
Creates a new zone by copying the configuration of the current zone.
copy-from
Creates a new zone by copying the configuration of the specified zone.
zone-name
Name of an existing zone.
snapshot-id
(Optional) Identifier of an existing snapshot. See the "Displaying Snapshots" section on page 7-15 for more information.
The following example shows how to create a new zone from the current zone:
user@DETECTOR-conf-zone-scannet# zone mailserver copy-from-thisuser@DETECTOR-conf-zone-mailserver#When you enter the zone command, the Detector enters the configuration mode of the new zone. The Detector marks the policies of the new zone as untuned (not tuned to zone-specific values). We recommend that you perform the threshold tuning phase of the learning process to tune the policy thresholds to the zone traffic (see the "Activating the Threshold Tuning Phase" section on page 7-6). If the traffic characteristics of the new zone are identical or very similar to the traffic characteristics of the originating zone, you can mark the policy thresholds as tuned (see the "Marking the Policies as Tuned" section on page 7-10).
Configuring Zone Attributes
Configure the attributes of a zone by performing the following steps:
Step 1
To enter zone configuration mode, use one of the following commands:
•
•
The zone-name argument specifies the name of an existing zone.
Note
Step 2
ip address [exclude] ip-addr [ip-mask]You must define at least one IP address that is not excluded to enable the Detector to learn the zone traffic and detect the zone.
See the "Configuring the Zone IP Address Range" section for more information.
Step 3
description stringThe maximum string length is 80 alphanumeric characters. If you use spaces in the expression, enclose the expression in quotation marks (" ").
To modify a zone description, reenter the zone description. The new description overrides the previous description.
Step 4
The configuration information consists of CLI commands that are executed to configure the Detector with the current settings. Refer to the specific command entries for more information.
The following example shows how to create a new zone and configure the zone attributes. The zone IP address range is configured to 192.168.100.32/27, but the IP address 192.168.100.50 is excluded from the zone IP address range.
user@DETECTOR-conf# zone scannetuser@DETECTOR-conf-zone-scannet# ip address 192.168.100.32 255.255.255.224user@DETECTOR-conf-zone-scannet# ip address exclude 192.168.100.50user@DETECTOR-conf-zone-scannet# description Demonstration zoneuser@DETECTOR-conf-zone-scannet# show running-configConfiguring the Zone IP Address Range
You must configure at least one IP address that is not excluded before you can activate zone anomaly detection, but you can add or delete IP addresses from the zone IP address range at any time. You can configure a large subnet and then exclude specific IP addresses from that subnet so that they are not part of the zone IP address range.
To configure the zone IP address, use the following command in zone configuration mode:
ip address [exclude] ip-addr [ip-mask]
Table 4-4 provides the arguments and keywords for the ip address command.
The following example shows how to configure the zone IP address range to 192.168.100.32/27 but exclude IP address 192.168.100.50 from the zone IP address range:
user@DETECTOR-conf-zone-scannet# ip address 192.168.100.32 255.255.255.224user@DETECTOR-conf-zone-scannet# ip address exclude 192.168.100.50If you modify the zone IP address range, perform one or both of the following tasks to update the zone configuration policies and policy thresholds:
•
•
–
Caution
See the "Enabling the Detect and Learn Function" section on page 7-11 and "Marking the Policies as Tuned" section on page 7-10 for more information.
–
To delete zone IP addresses, use the no form of the command.
To delete excluded IP addresses, use the no ip address exclude command.
To delete all zone IP addresses and exclude IP addresses, use the no ip address * command.
Synchronizing Zone Configurations with a Guard
The synchronization process allows you to maintain a copy of a zone configuration on both the Detector and the Guards that you associate with the Detector. You can also use the synchronization process to maintain copies of the Detector zone configurations on a remote server.
The synchronization process, which you perform from the Detector only, enables the following operations:
•
•
•
You can manually synchronize zone configurations or you can configure the Detector to perform the following tasks automatically:
•
•
Using the synchronization process, you can create, configure, and modify a zone on the Detector and then update the Guard with the same zone information. The synchronization process also enables the Detector to continuously learn the zone traffic characteristics to keep the zone policies updated on both itself and the Guard. When you let the Detector do the learning for the Guard, you avoid having to divert the zone traffic to the Guard.
This section contains the following topics:
•
•
•
•
•
•
•
•
•
Understanding the Configuration Guidelines for Synchronization
To synchronize zones between the Detector and a Guard, follow these guidelines:
•
•
•
•
•
Creating a Zone for Synchronization
To synchronize a zone configuration between the Detector and a Guard, you must create the zone on the Detector using one of the Guard zone templates which have two sets of definitions; one for the Guard and one for the Detector. See Table 4-1 for more information about the zone templates.
When creating a zone using one the Guard zone templates, you use the following configuration modes to configure the zone:
•
user@DETECTOR-conf-zone-scannet#•
user@DETECTOR-conf-zone-scannet(guard)#•
If you modify a zone attribute that is common to both the Guard and the Detector, the change applies to both sets of definitions. For example, if you modify the zone IP address in zone configuration mode, the new IP address is also modified in the zone definition for the Guard. You can display the new zone definition for the Guard in guard configuration mode. If you change the operation state of a policy in guard configuration mode, the operation state is also modified in the zone definition of the Detector.
To create and configure a zone for synchronization, perform the following steps:
Step 1
When you create a new zone using a Guard zone templates, the Detector displays (Guard/Detector) next to the zone ID field in the output of the show command in zone configuration mode.
Step 2
Step 3
•
•
•
The zone-name argument specifies the name of an existing zone.The Detector enters the guard configuration mode. The CLI prompt indicates the mode by adding the word guard in parentheses (guard) to the prompt.
The following example shows how to enter guard configuration mode:
user@DETECTOR-conf-zone-scannet# guard-confuser@DETECTOR-conf-zone-scannet(guard)#The guard configuration mode allows you to configure all zone attributes that are unique to the Guard, such as user filters, filter termination, and a policy or a filter action of drop. See the Cisco Guard Configuration Guide for more information.
Configuring the Automatic Zone Synchronization and Export Parameters
You can configure the Detector to perform the following tasks automatically:
•
–
–
If you do not define any Guards on the zone remote Guard list, then the Detector synchronizes the zone configuration with the remote Guards that you define in the Detector default remote Guard list. If synchronization with one of the remote Guards fails, the Detector continues to the next remote Guard on the list.
If both the zone remote Guard list and the Detector default remote Guard list are empty, the Detector does not synchronize the zone configuration.
If a zone with the same name exists on the Guard, the new configuration replaces the existing one.
•
If both the zone remote server list and the Detector default remote server list are empty, the Detector does not export the zone configuration.
To enable automatic synchronization and export of a zone configuration, use the following command in zone configuration mode:
learning-params sync {accept | remote-activate}
Table 4-5 provides the keywords for the learning-params sync command.
The following example shows how to automatically synchronize and export the zone configuration each time that the Detector accepts the results of the threshold-tuning phase of the learning process:
user@DETECTOR-conf-zone-scannet# learning-params sync accept
To disable automatic synchronization and export functions, use the no learning-params sync command.
Synchronizing a Zone Configuration from the Guard to the Detector
You can enable the Detector to copy a zone configuration from a Guard to the Detector. If the zone already exists on the Detector, the new configuration from the Guard overrides the existing one.
Synchronizing a zone configuration from the Guard to the Detector may be required if you manually modify the zone policies on the Guard to adjust them for attack characteristics and would like to update the Detector with the changes. You can set certain policy thresholds as fixed or set a fixed multiplier for policy thresholds to ensure the following:
•
•
See the "Setting the Threshold as Fixed" section on page 6-14 and the "Configuring a Threshold Multiplier" section on page 6-15 for more information.
To synchronize the zone configuration and policies from the Guard to the Detector, perform the following steps:
Step 1
Step 2
•
•
Table 4-6 provides the arguments for the sync command.
Step 3
For more information, see Chapter 8, "Detecting Zone Traffic Anomalies," and the "Synchronizing Zone Configurations with a Guard" section.
The following example shows how to deactivate the zone scannet and synchronize the zone configuration from a Guard with an IP address of 192.168.55.10 to the Detector. It then shows how to reactivate the zone.
user@DETECTOR-conf-zone-scannet# deactivateuser@DETECTOR-conf-zone-scannet# sync 192.168.55.10 localuser@DETECTOR-conf-zone-scannet# detect learningSynchronizing a Zone Configuration from the Detector to the Guard
You can synchronize aDetector zone configuration with the zone on the Guard to ensure that the zone configuration and policies on the Guard are updated when the Guard activates zone protection. This process allows you to configure the zone once on the Detector, continuously learn the zone traffic characteristics, and maintain the same zone configuration and policies on the Guard without constantly diverting the zone traffic to the Guard.
The Detector copies the configuration of the zone to the Guard. If a zone with the same name exists on the Guard, the new configuration replaces the existing one.
Note
Synchronize the zone configuration and policies from the Detector by entering one of the following commands:
•
(in global mode)•
(in zone configuration mode)Table 4-7 provides the arguments and keywords for the sync command.
The following example shows how to synchronize the zone configuration to all remote Guards in the zone remote Guard list:
user@DETECTOR# sync zone scannet local remote-guardsThe following example shows how to synchronize the zone configuration to a remote Guard with an IP address of 192.168.100.5:
user@DETECTOR-conf-zone-scannet# sync local 192.168.100.5Synchronizing a Zone Configuration Offline
You can synchronize a Detector zone configuration with a Guard by using the offline synchronization procedure that is described in this section. You may need to synchronize a zone configuration offline if one of the following conditions applies:
•
•
To synchronize a zone configuration offline, you must first export the zone configuration from the Detector to a network server using FTP, SFTP, or SCP, and then import the zone configuration manually from the network server to the Guard.
To perform an offline synchronization of a zone configuration on the Detector with the Guard, you must perform the following tasks:
•
•
To synchronize the zone on the Detector with the zone configuration on the Guard configuration offline, perform the following steps:
Step 1
Step 2
•
•
–
–
See Table 4-9 for a descriptions of the copy zone command arguments and keywords. See "Exporting a Zone Configuration Manually to a Network Server" section for more information.
Step 3
Note
•
•
•
Table 4-8 describes the arguments and keywords for the copy command.
See the "Importing and Updating the Configuration" section on page 12-4 for more information.
Note
Exporting a Zone Configuration Automatically to a Network Server
You can configure the Detector to export the zone configuration automatically to a network server. The Detector exports the zone configuration each time that the results of the threshold-tuning phase of the learning process are accepted (see the "Configuring Periodic Actions" section on page 7-8 for more information about when the results of the threshold-tuning phase of the learning process are accepted).
To export the zone configuration automatically, you must define the network server, which can be an FTP, SFTP, or SCP network server. You can configure the network server in the following lists:
•
•
To configure the Detector to automatically export the zone configuration to a network server, perform the following steps:
Step 1
If you configured the network server using SFTP or SCP, you must configure the SSH key that the Detector uses for SFTP and SCP communication (see the "Configuring the Keys for SFTP and SCP Connections" section on page 3-27).
Step 2
export sync-config file-server-nameThe file-server-name argument specifies the name of the network server that you specified in Step 1. To remove a network server from the remote server list, use the no form of the command.
Step 3
export sync-config file-server-nameThe file-server-name argument specifies the name of the network server that you specified in Step 1. To remove a network server from the remote server list, use the no form of the command.
Step 4
The following example shows how to add a network server to the zone remote server list:
user@DETECTOR-conf-zone-scannet# export sync-config Corp-FTP-ServerTo display the default list of network servers to which the Detector exports zone configuration, use the show sync-config file-servers command in configuration mode.
To display the zone remote server list, use the show sync-config file-servers command in zone configuration mode.
Exporting a Zone Configuration Manually to a Network Server
You can manually export the zone configuration to a network server.
Export the zone configuration to a network server by entering one of the following commands in global mode:
•
•
•
•
Table 4-9 provides the arguments for the copy guard-running-config command.
Table 4-9 Arguments and Keywords for the copy guard-running-config Command
zone zone-name
Specifies the name of an existing zone.
guard-running-config
Exports the portion of the zone configuration that is required to configure the zone on a Guard.
ftp
Specifies FTP.
sftp
Specifies SFTP.
scp
Specifies SCP.
server
IP address of the network server. Enter the IP address in dotted-decimal notation (for example, enter 192.168.10.2).
full-file-name
Complete name of the file. If you do not specify a path, the server saves the file in your home directory.
login
(Optional) Server login name.
The login argument is optional when you define an FTP server. When you do not enter a login name, the FTP server assumes an anonymous login and does not prompt you for a password.
password
(Optional) Password for the remote FTP server. If you do not enter the password, the Detector prompts you for it.
file-server-name
Name of a network server to which to export the configuration file. You must configure the network server using the file-server command.
If you configured the network server using SFTP or SCP, you must configure the SSH key that the Detector uses for SFTP and SCP communication. See the "Configuring File Servers" section on page 12-1 for more information.
dest-file-name
Name of the configuration file on the remote server. The Detector saves the configuration file on the network server using the destination filename in the directory that you defined for the network server when you entered the file-server command.
*
Exports only the portion of the zone configuration that is required to configure the zone on the Guard to all the network servers that are defined in the zone remote server list and the default remote server list. See the "Exporting a Zone Configuration Automatically to a Network Server" section for more information.
Because SFTP and SCP rely on SSH for secure communication, if you do not configure the key that the Detector uses before you enter the copy command with the sftp or scp option, the Detector prompts you for the password. See the "Configuring the Keys for SFTP and SCP Connections" section on page 3-27 for more information about how to configure the key that the Detector uses for secure communication.
The following example shows how to export the zone configuration to an FTP server:
user@DETECTOR-conf# copy zone scannet guard-running-config ftp 10.0.0.191 /root/ConfigFiles/scannet.txt <user> <password>Example Synchronization Scenario
This example scenario shows how to synchronize a zone configuration on the Detector with a zone configuration on the Guard to protect the zone while the Detector is learning the zone traffic characteristics:
1.
For more information, see the "Creating a New Zone from a Zone Template" section.
2.
For more information, see the "Configuring the Default Remote Guard List" section on page 8-7 and the "Configuring the Zone Remote Guard Lists" section on page 8-8.
3.
4.
5.
For more information, see the "Configuring Periodic Actions" section on page 7-8.
6.
Use the learning-params sync command to configure the Detector to synchronize the zone configuration with the Guard. For more information, see the "Configuring the Automatic Zone Synchronization and Export Parameters" section.
7.
Use the learning-params sync command.
For more information, see the "Configuring the Automatic Zone Synchronization and Export Parameters" section.
When the Detector detects an attack on the zone, it performs the following actions:
•
•
•
You can modify the zone policies on the Guard when the attack is in progress.
The Detector polls the Guard constantly. When the Detector identifies that the Guard has deactivated zone protection (the Guard deactivates zone protection when the attack ends) and additional traffic anomalies do not exist, then the Detector reactivates zone anomaly detection and the learning process.
8.
For more information, see the "Setting the Threshold as Fixed" section on page 6-14 and the "Configuring a Threshold Multiplier" section on page 6-15.
To synchronize the zone configuration and policies from the Guard to the Detector, perform the following actions:
•
•
•
For more information, see the "Synchronizing a Zone Configuration from the Guard to the Detector" section and Chapter 8, "Detecting Zone Traffic Anomalies."
