AsyncOS 8.7 for Cisco Web Security Appliances User Guide

455 Pages·2015·3.44 MB·English

AsyncOS 8.7 for Cisco Web Security
Appliances User Guide
Published: March 31, 2015
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AsyncOS 8.7 for Cisco Web Security Appliances User Guide
© 2015 Cisco Systems, Inc. All rights reserved.
C O N T E N T S
CHAPTER 1 Introduction to the Product and the Release 1-1
Introduction to the Web Security Appliance 1-1
What’s New 1-1
What’s New in Cisco AsyncOS 8.7 1-2
Requirements and Restrictions for AsyncOS 8.7 1-2
What’s New in Cisco AsyncOS 8.5 1-2
Using the Appliance Web Interface 1-4
Web Interface Browser Requirements 1-4
Accessing the Appliance Web Interface 1-4
Committing Changes in the Web Interface 1-5
Clearing Changes in the Web Interface 1-5
The Cisco SensorBase Network 1-5
SensorBase Benefits and Privacy 1-5
Enabling Participation in The Cisco SensorBase Network 1-6
CHAPTER 2 Connect, Install, and Configure 2-1
Overview of Connect, Install, and Configure 2-1
Deploying a Virtual Appliance 2-1
Migrating from a Physical to a Virtual Appliance 2-2
Task Overview for Connecting, Installing, and Configuring 2-2
Connecting the Appliance 2-2
Gathering Setup Information 2-4
System Setup Wizard 2-6
System Setup Wizard Reference Information 2-7
Network / System Settings 2-7
Network / Network Context 2-8
Network / Network Interfaces and Wiring 2-9
Network / Routes for Management and Data Traffic 2-9
Network / Transparent Connection Settings 2-10
Network / Administrative Settings 2-10
Security / Security Settings 2-12
Upstream Proxies 2-12
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Upstream Proxies Task Overview 2-13
Creating Proxy Groups for Upstream Proxies 2-13
Network Interfaces 2-14
IP Address Versions 2-14
Enabling or Changing Network Interfaces 2-15
Configuring Failover Groups for High Availability 2-17
Add Failover Group 2-17
Edit High Availability Global Settings 2-18
View Status of Failover Groups 2-18
Using the P2 Data Interface for Web Proxy Data 2-18
Configuring TCP/IP Traffic Routes 2-19
Modifying the Default Route 2-20
Adding a Route 2-21
Saving and Loading Routing Tables 2-21
Deleting a Route 2-21
Configuring Transparent Redirection 2-21
Specifying a Transparent Redirection Device 2-21
Configuring WCCP Services 2-22
Increasing Interface Capacity Using VLANs 2-25
Configuring and Managing VLANs 2-25
Redirect Hostname and System Hostname 2-29
Changing the Redirect Hostname 2-30
Changing the System Hostname 2-30
Configuring SMTP Relay Host Settings 2-30
Configuring an SMTP Relay Host 2-31
DNS Settings 2-31
Split DNS 2-31
Clearing the DNS Cache 2-32
Editing DNS Settings 2-32
Troubleshooting Connect, Install, and Configure 2-33
CHAPTER 3 Connect the Appliance to a Cisco Cloud Web Security Proxy 3-1
Overview of Connect the Appliance to a Cloud Web SecurityProxy 3-1
Cloud Connector versus Standard Mode 3-2
Documentation Links 3-4
Deployment 3-4
Configuring the Cloud Connector 3-5
Step 1. Access the Web Interface for the Web Security Appliance 3-5
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Step 2. Accept the License Agreement and Begin Setup. 3-5
Step 3. Configure System Settings: 3-5
Step 4. Set the Appliance Mode 3-5
Step 5. Configure Cloud Connector Settings 3-6
Step 6. Configure Network Interfaces and Wiring 3-6
Step 7. Configure Routes for Management and Data Traffic 3-7
Step 8. Configure Transparent Connection Settings 3-7
Step 9. Configure Administrative Settings 3-8
Step 10. Review and Install 3-8
Directory Group Policies in the Cloud 3-8
Sending Directory Groups to the Cloud 3-8
Bypassing the Cloud Proxy Server 3-9
FTP and HTTPS 3-9
FTP 3-9
HTTPS 3-9
Preventing Loss of Secure Data 3-10
Cloud Connector Logs 3-10
Subscribing to the Cloud Connector Logs 3-10
Identification Profiles and Authentication 3-11
Identifying Machines for Policy Application 3-11
Guest Access for Unauthenticated Users 3-12
Configuration Modes 3-12
Switching to Cloud Connector Mode 3-12
CHAPTER 4 Intercepting Web Requests 4-1
Overview of Intercepting Web Requests 4-1
Tasks for Intercepting Web Requests 4-2
Best Practices for Intercepting Web Requests 4-2
Web Proxy Options for Intercepting Web Requests 4-3
Configuring Web Proxy Settings 4-3
Web Proxy Cache 4-5
Clearing the Web Proxy Cache 4-5
Removing URLs from the Web Proxy Cache 4-6
Specifying Domains or URLs that the Web Proxy never Caches 4-6
Choosing The Web Proxy Cache Mode 4-7
Web Proxy IP Spoofing 4-8
Web Proxy Custom Headers 4-9
Adding Custom Headers To Web Requests 4-9
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Web Proxy Bypassing 4-10
Web Proxy Bypassing for Web Requests 4-10
Configuring Web Proxy Bypassing for Web Requests 4-10
Configuring Web Proxy Bypassing for Applications 4-10
Web Proxy Usage Agreement 4-11
Client Options for Redirecting Web Requests 4-11
Using PAC Files with Client Applications 4-11
Options For Publishing Proxy Auto-Config (PAC) Files 4-11
Client Options For Finding Proxy Auto-Config (PAC) Files 4-12
Automatic PAC File Detection 4-12
Hosting PAC Files on the Web Security Appliance 4-12
Specifying PAC Files in Client Applications 4-13
Configuring a PAC File Location Manually in Clients 4-13
Detecting the PAC File Automatically in Clients 4-13
FTP Proxy Services 4-14
Overview of FTP Proxy Services 4-14
Enabling and Configuring the FTP Proxy 4-14
SOCKS Proxy Services 4-16
Overview of SOCKS Proxy Services 4-16
Enabling Processing of SOCKS Traffic 4-16
Configuring the SOCKS Proxy 4-17
Creating SOCKS Policies 4-17
Troubleshooting Intercepting Requests 4-18
CHAPTER 5 Acquire End-User Credentials 5-1
Overview of Acquire End-User Credentials 5-1
Authentication Task Overview 5-2
Authentication Best Practices 5-2
Authentication Planning 5-2
Active Directory/Kerberos 5-3
Active Directory/Basic 5-4
Active Directory/NTLMSSP 5-5
LDAP/Basic 5-5
Identifying Users Transparently 5-5
Understanding Transparent User Identification 5-6
Rules and Guidelines 5-9
Configuring Transparent User Identification 5-9
Using the CLI to Configure Advanced Transparent User Identification Settings 5-9
Configuring Single-Sign-on 5-10
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Authentication Realms 5-10
External Authentication 5-11
Configuring External Authentication through an LDAP Server 5-11
Enabling RADIUS External Authentication 5-11
Creating an Active Directory Realm for Kerberos Authentication Scheme 5-12
Creating an Active Directory Authentication Realm (NTLMSSP and Basic) 5-14
Creating an LDAP Authentication Realm 5-16
About Deleting Authentication Realms 5-20
Configuring Global Authentication Settings 5-20
Authentication Sequences 5-25
About Authentication Sequences 5-26
Creating Authentication Sequences 5-26
Editing And Reordering Authentication Sequences 5-27
Deleting Authentication Sequences 5-27
Failed Authentication 5-27
About Failed Authentication 5-28
Bypassing Authentication 5-28
Permitting Unauthenticated Traffic While Authentication Service is Unavailable 5-28
Granting Guest Access After Failed Authentication 5-29
Define an Identification Profile that Supports Guest Access 5-29
Use an Identification Profile that Supports Guest Access in a Policy 5-29
Configure How Guest User Details are Logged 5-30
Failed Authorization: Allowing Re-Authentication with Different Credentials 5-30
About Allowing Re-Authentication with Different Credentials 5-30
Allowing Re-Authentication with Different Credentials 5-30
Tracking Identified Users 5-31
Supported Authentication Surrogates for Explicit Requests 5-31
Supported Authentication Surrogates for Transparent Requests 5-31
Tracking Re-Authenticated Users 5-32
Credentials 5-32
Tracking Credentials for Reuse During a Session 5-32
Authentication and Authorization Failures 5-33
Credential Format 5-33
Credential Encryption for Basic Authentication 5-33
About Credential Encryption for Basic Authentication 5-33
Configuring Credential Encryption 5-33
Troubleshooting Authentication 5-34
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CHAPTER 6 Classify End-Users and Client Software 6-1
Overview of Classify Users and Client Software 6-1
Classify Users and Client Software: Best Practices 6-2
Identification Profile Criteria 6-2
Classifying Users and Client Software 6-3
Enable/Disable an Identity 6-8
Identification Profiles and Authentication 6-8
Troubleshooting Identification Profiles 6-9
CHAPTER 7 SaaS Access Control 7-1
Overview of SaaS Access Control 7-1
Configuring the Appliance as an Identity Provider 7-2
Using SaaS Access Control and Multiple Appliances 7-4
Creating SaaS Application Authentication Policies 7-4
Configuring End-user Access to the Single Sign-on URL 7-6
CHAPTER 8 Integrate the Cisco Identity Services Engine 8-1
Overview of the Identity Services Engine Service 8-1
Identity Services Engine Certificates 8-1
Tasks for Integrating the Identity Services Engine Service 8-2
Connect to the Identity Services Engine Service 8-4
Troubleshooting Identity Services Engine Problems 8-4
CHAPTER 9 Classify URLs for Policy Application 9-1
Overview of Categorizing URL Transactions 9-1
Categorization of Failed URL Transactions 9-2
Enabling the Dynamic Content Analysis Engine 9-2
Uncategorized URLs 9-2
Matching URLs to URL Categories 9-3
Reporting Uncategorized and Misclassified URLs 9-3
URL Categories Database 9-3
Configuring the URL Filtering Engine 9-4
Managing Updates to the Set of URL Categories 9-4
Understanding the Impacts of URL Category Set Updates 9-5
Effects of URL Category Set Changes on Policy Group Membership 9-5
Effects of URL Category Set Updates on Filtering Actions in Policies 9-5
Merged Categories - Examples 9-6
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Controlling Updates to the URL Category Set 9-7
Manually Updating the URL Category Set 9-7
Default Settings for New and Changed Categories 9-8
Verifying Existing Settings and/or Making Changes 9-8
Receiving Alerts About Category and Policy Changes 9-8
Responding to Alerts about URL Category Set Updates 9-8
Filtering Transactions Using URL Categories 9-9
Configuring URL Filters for Access Policy Groups 9-9
Configuring URL Filters for Decryption Policy Groups 9-11
Configuring URL Filters for Data Security Policy Groups 9-12
Creating and Editing Custom URL Categories 9-13
Filtering Adult Content 9-15
Enforcing Safe Searches and Site Content Ratings 9-15
Logging Adult Content Access 9-16
Redirecting Traffic in the Access Policies 9-17
Logging and Reporting 9-17
Warning Users and Allowing Them to Continue 9-17
Configuring Settings for the End-User Filtering Warning Page 9-18
Creating Time Based URL Filters 9-19
Viewing URL Filtering Activity 9-19
Understanding Unfiltered and Uncategorized Data 9-19
Access Log File 9-20
Regular Expressions 9-20
Forming Regular Expressions 9-20
Guidelines for Avoiding Validation Failures 9-21
Regular Expression Character Table 9-22
URL Category Descriptions 9-23
CHAPTER 10 Create Policies to Control Internet Requests 10-1
Overview of Policies: Control Intercepted Internet Requests 10-1
Managing Web Requests Through Policies Task Overview 10-2
Managing Web Requests Through Policies Best Practices 10-2
Policies 10-2
Policy Types 10-3
Policy Order 10-5
Creating a Policy 10-5
Adding and Editing Secure Group Tags for a Policy 10-8
Policy Configuration 10-8
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Block, Allow, or Redirect Transaction Requests 10-9
Client Applications 10-10
About Client Applications 10-10
Using Client Applications in Policies 10-10
Exempting Client Applications from Authentication 10-12
Time Ranges and Volume Quotas 10-12
Volume Quota Calculations 10-13
Time Quota Calculations 10-13
Defining Time and Volume Quotas 10-13
Access Control by URL Category 10-14
Creating Custom URL Categories 10-14
Using URL Categories to Identify Web Requests 10-15
Using URL Categories to Action Web Request 10-16
Remote Users 10-16
About Remote Users 10-17
Configuring Identification for Remote Users 10-17
Configuring Identification of Remote Users 10-17
Display Remote User Status and Statistics for ASAs 10-18
Troubleshooting Policies 10-19
CHAPTER 11 Create Decryption Policies to Control HTTPSTraffic 11-1
Overview of Create Decryption Policies to Control HTTP Traffic 11-1
Managing HTTPS Traffic through Decryption Policies Task Overview 11-2
Managing HTTPS Traffic through Decryption Policies BestPractices 11-2
Decryption Policies 11-2
Enabling the HTTPS Proxy 11-3
Controlling HTTPS Traffic 11-4
Configuring Decryption Options 11-4
Authentication and HTTPS Connections 11-5
Root Certificates 11-5
Managing Certificate Validation and Decryption for HTTPS 11-6
Valid Certificates 11-6
Invalid Certificate Handling 11-6
Uploading a Root Certificate and Key 11-7
Generating a Certificate and Key 11-7
Configuring Invalid Certificate Handling 11-8
Options for Certificate Revocation Status Checking 11-9
Enabling Real-Time Revocation Status Checking 11-9
Trusted Root Certificates 11-10
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