User Guide for AsyncOS 9.0.1 for Cisco Web Security Appliances

498 Pages·2017·4.24 MB·English

by  Cisco Systems Inc.

AsyncOS 9.0.1 for Cisco Web Security
Appliances User Guide
Published: January 27, 2016
Revised: August 18, 2017
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This product includes cryptographic software written by Eric Young ([email protected]).
This product includes software written by Tim Hudson ([email protected]).
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AsyncOS 9.0.1 for Cisco Web Security Appliances User Guide
© 2017 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 9.0.1 1-1
What’s New in Cisco AsyncOS 9.0.1-162 (GD) 1-1
What’s New in Cisco AsyncOS 9.0.1-161 (GD - for physical appliances only) 1-2
What’s New in Cisco AsyncOS 9.0.1-135 (ED) 1-2
Related Topics 1-2
Using the Appliance Web Interface 1-2
Web Interface Browser Requirements 1-3
Enabling Access to the Web Interface on Virtual Appliances 1-3
Accessing the Appliance Web Interface 1-3
Committing Changes in the Web Interface 1-4
Clearing Changes in the Web Interface 1-4
The Cisco SensorBase Network 1-4
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 2-2
Migrating from a Physical to a Virtual Appliance 2-2
Comparison of Modes of Operation 2-2
Task Overview for Connecting, Installing, and Configuring 2-6
Connecting the Appliance 2-6
Gathering Setup Information 2-8
System Setup Wizard 2-10
System Setup Wizard Reference Information 2-11
Network / System Settings 2-11
Network / Network Context 2-12
Network / Cloud Connector Settings 2-12
Network / Network Interfaces and Wiring 2-13
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Network / Layer 4 Traffic Monitor Wiring 2-13
Network / Routes for Management and Data Traffic 2-14
Network / Transparent Connection Settings 2-14
Network /Administrative Settings 2-15
Security / Security Settings 2-15
Upstream Proxies 2-16
Upstream Proxies Task Overview 2-16
Creating Proxy Groups for Upstream Proxies 2-16
Network Interfaces 2-17
IP Address Versions 2-18
Enabling or Changing Network Interfaces 2-18
Configuring Failover Groups for High Availability 2-20
Add Failover Group 2-20
Edit High Availability Global Settings 2-21
View Status of Failover Groups 2-21
Using the P2 Data Interface for Web Proxy Data 2-21
Configuring TCP/IP Traffic Routes 2-22
Modifying the Default Route 2-23
Adding a Route 2-24
Saving and Loading Routing Tables 2-24
Deleting a Route 2-24
Configuring Transparent Redirection 2-24
Specifying a Transparent Redirection Device 2-24
Configuring WCCP Services 2-25
Increasing Interface Capacity Using VLANs 2-28
Configuring and Managing VLANs 2-28
Redirect Hostname and System Hostname 2-30
Changing the Redirect Hostname 2-31
Changing the System Hostname 2-31
Configuring SMTP Relay Host Settings 2-31
Configuring an SMTP Relay Host 2-32
DNS Settings 2-32
Split DNS 2-32
Clearing the DNS Cache 2-32
Editing DNS Settings 2-33
Troubleshooting Connect, Install, and Configure 2-34
CHAPTER 3 Connect the Appliance to a Cisco Cloud Web Security Proxy 3-1
How to Configure and Use Features in Cloud Connector Mode 3-1
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Deployment in Cloud Connector Mode 3-2
Configuring the Cloud Connector 3-2
Controlling Web Access Using Directory Groups in the Cloud 3-5
Bypassing the Cloud Proxy Server 3-5
Partial Support for FTP and HTTPS in Cloud Connector Mode 3-5
Preventing Loss of Secure Data 3-6
Viewing Group and User Names and IP Addresses 3-6
Subscribing to Cloud Connector Logs 3-6
Identification Profiles and Authentication with Cloud Web Security Connector 3-7
Identifying Machines for Policy Application 3-7
Guest Access for Unauthenticated Users 3-8
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
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
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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 4-17
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 for Transparent User Identification 5-8
Configuring Transparent User Identification 5-9
Using the CLI to Configure Advanced Transparent User Identification Settings 5-9
Configuring Single-Sign-on 5-10
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 5-11
How to Create an Active Directory Authentication Realm (NTLMSSP and Basic) 5-14
Prerequisites for Creating an Active Directory Authentication Realm (NTLMSSP and Basic) 5-14
About Using Multiple NTLM Realms and Domains 5-14
Creating an Active Directory Authentication Realm (NTLMSSP and Basic) 5-15
Creating an LDAP Authentication Realm 5-16
About Deleting Authentication Realms 5-21
Configuring Global Authentication Settings 5-21
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Authentication Sequences 5-26
About Authentication Sequences 5-27
Creating Authentication Sequences 5-27
Editing And Reordering Authentication Sequences 5-28
Deleting Authentication Sequences 5-28
Failed Authentication 5-28
About Failed Authentication 5-29
Bypassing Authentication with Problematic User Agents 5-29
Bypassing Authentication 5-31
Permitting Unauthenticated Traffic While Authentication Service is Unavailable 5-31
Granting Guest Access After Failed Authentication 5-31
Define an Identification Profile that Supports Guest Access 5-32
Use an Identification Profile that Supports Guest Access in a Policy 5-32
Configure How Guest User Details are Logged 5-32
Failed Authorization: Allowing Re-Authentication with Different Credentials 5-33
About Allowing Re-Authentication with Different Credentials 5-33
Allowing Re-Authentication with Different Credentials 5-33
Tracking Identified Users 5-33
Supported Authentication Surrogates for Explicit Requests 5-34
Supported Authentication Surrogates for Transparent Requests 5-34
Tracking Re-Authenticated Users 5-34
Credentials 5-35
Tracking Credentials for Reuse During a Session 5-35
Authentication and Authorization Failures 5-36
Credential Format 5-36
Credential Encryption for Basic Authentication 5-36
About Credential Encryption for Basic Authentication 5-36
Configuring Credential Encryption 5-36
Troubleshooting Authentication 5-37
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 6-10
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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
About pxGrid 8-1
About the ISE Server Deployment and Failover 8-2
Identity Services Engine Certificates 8-2
Using Self-signed Certificates 8-3
Using CA-signed Certificates 8-3
Tasks for Certifying and Integrating the ISE Service 8-3
Connect to the ISE Services 8-6
Troubleshooting Identity Services Engine Problems 8-7
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
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
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Filtering Transactions Using URL Categories 9-9
Configuring URL Filters for Access Policy Groups 9-9
Exceptions to Blocking for Embedded and Referred Content 9-11
Configuring URL Filters for Decryption Policy Groups 9-12
Configuring URL Filters for Data Security Policy Groups 9-13
Creating and Editing Custom URL Categories 9-14
Filtering Adult Content 9-16
Enforcing Safe Searches and Site Content Ratings 9-17
Logging Adult Content Access 9-18
Redirecting Traffic in the Access Policies 9-18
Logging and Reporting 9-19
Warning Users and Allowing Them to Continue 9-19
Configuring Settings for the End-User Filtering Warning Page 9-19
Creating Time Based URL Filters 9-20
Viewing URL Filtering Activity 9-21
Understanding Unfiltered and Uncategorized Data 9-21
URL Category Logging in Access Logs 9-21
Regular Expressions 9-21
Forming Regular Expressions 9-22
Guidelines for Avoiding Validation Failures 9-23
Regular Expression Character Table 9-24
URL Category Descriptions 9-25
CHAPTER 10 Create Policies to Control Internet Requests 10-1
Overview of Policies: Control Intercepted Internet Requests 10-1
Intercepted HTTP/HTTPS Request Processing 10-2
Managing Web Requests Through Policies Task Overview 10-3
Managing Web Requests Through Policies Best Practices 10-3
Policies 10-3
Policy Types 10-4
Policy Order 10-6
Creating a Policy 10-7
Adding and Editing Secure Group Tags for a Policy 10-10
Policy Configuration 10-10
Block, Allow, or Redirect Transaction Requests 10-14
Client Applications 10-14
About Client Applications 10-14
Using Client Applications in Policies 10-15
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Exempting Client Applications from Authentication 10-16
Time Ranges and Quotas 10-16
Time Ranges for Policies and Acceptable Use Controls 10-16
Creating a Time Range 10-16
Time and Volume Quotas 10-17
Volume Quota Calculations 10-18
Time Quota Calculations 10-18
Defining Time and Volume Quotas 10-18
Access Control by URL Category 10-19
Using URL Categories to Identify Web Requests 10-19
Using URL Categories to Action Web Request 10-19
Remote Users 10-20
About Remote Users 10-20
How to Configure Identification of Remote Users 10-21
Configuring Identification of Remote Users 10-21
Display Remote User Status and Statistics for ASAs 10-22
Troubleshooting Policies 10-23
CHAPTER 11 Create Decryption Policies to Control HTTPSTraffic 11-1
Overview of Create Decryption Policies to Control HTTPS 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 11-4
Controlling HTTPS Traffic 11-6
Configuring Decryption Options 11-8
Authentication and HTTPS Connections 11-8
Root Certificates 11-8
Managing Certificate Validation and Decryption for HTTPS 11-9
Valid Certificates 11-9
Invalid Certificate Handling 11-10
Uploading a Root Certificate and Key 11-10
Generating a Certificate and Key for the HTTPS Proxy 11-11
Configuring Invalid Certificate Handling 11-11
Options for Certificate Revocation Status Checking 11-12
Enabling Real-Time Revocation Status Checking 11-13
Trusted Root Certificates 11-13
Adding Certificates to the Trusted List 11-14
Removing Certificates from the Trusted List 11-14
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