User Guide for AsyncOS 9.1 For Cisco Web Security Appliances

450 Pages·2016·3.1 MB·English

AsyncOS 9.1 for Cisco Web Security
Appliances User Guide
Published: March 14, 2016
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AsyncOS 9.1 for Cisco Web Security Appliances User Guide
© 2016 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
Using the Appliance Web Interface 1-1
Web Interface Browser Requirements 1-2
Enabling Access to the Web Interface on Virtual Appliances 1-2
Accessing the Appliance Web Interface 1-2
Committing Changes in the Web Interface 1-3
Clearing Changes in the Web Interface 1-3
The Cisco SensorBase Network 1-3
SensorBase Benefits and Privacy 1-4
Enabling Participation in The Cisco SensorBase Network 1-4
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
Task Overview for Connecting, Installing, and Configuring 2-2
Connecting the Appliance 2-2
Gathering Setup Information 2-4
System Setup Wizard 2-5
System Setup Wizard Reference Information 2-6
Network / System Settings 2-6
2-7
Network / Network Interfaces and Wiring 2-7
2-7
Network / Routes for Management and Data Traffic 2-8
Network / Transparent Connection Settings 2-8
Network /Administrative Settings 2-8
Comparison of Modes of Operation 2-9
Upstream Proxies 2-9
Upstream Proxies Task Overview 2-10
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Creating Proxy Groups for Upstream Proxies 2-10
Network Interfaces 2-11
IP Address Versions 2-11
Enabling or Changing Network Interfaces 2-12
Configuring Failover Groups for High Availability 2-14
Add Failover Group 2-14
Edit High Availability Global Settings 2-15
View Status of Failover Groups 2-15
Using the P2 Data Interface for Web Proxy Data 2-15
Configuring TCP/IP Traffic Routes 2-16
Modifying the Default Route 2-17
Adding a Route 2-18
Saving and Loading Routing Tables 2-18
Deleting a Route 2-18
Configuring Transparent Redirection 2-18
Specifying a Transparent Redirection Device 2-18
Configuring WCCP Services 2-19
Increasing Interface Capacity Using VLANs 2-22
Configuring and Managing VLANs 2-22
Redirect Hostname and System Hostname 2-24
Changing the Redirect Hostname 2-25
Changing the System Hostname 2-25
Configuring SMTP Relay Host Settings 2-25
Configuring an SMTP Relay Host 2-26
DNS Settings 2-26
Split DNS 2-26
Clearing the DNS Cache 2-26
Editing DNS Settings 2-27
Troubleshooting Connect, Install, and Configure 2-28
CHAPTER 3 Connect the Appliance to a Cisco Cloud Web Security Proxy 3-1
Comparison of Cloud Connector Mode and Standard Mode 3-1
How to Configure and Use Features in Cloud Connector Mode 3-4
Deployment in Cloud Connector Mode 3-4
Configuring the Cloud Connector 3-5
Controlling Web Access Using Directory Groups in the Cloud 3-8
Bypassing the Cloud Proxy Server 3-8
Partial Support for FTP and HTTPS in Cloud Connector Mode 3-8
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Preventing Loss of Secure Data 3-9
Viewing Group and User Names and IP Addresses 3-9
Subscribing to Cloud Connector Logs 3-9
Identification Profiles and Authentication with Cloud Web Security Connector 3-10
Identifying Machines for Policy Application 3-10
Guest Access for Unauthenticated Users 3-11
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 4-5
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 4-8
Adding Custom Headers To Web Requests 4-8
Web Proxy Bypassing 4-9
Web Proxy Bypassing for Web Requests 4-9
Configuring Web Proxy Bypassing for Web Requests 4-10
Configuring Web Proxy Bypassing for Applications 4-10
Web Proxy Usage Agreement 4-10
Client Options for Redirecting Web Requests 4-10
Troubleshooting Intercepting Requests 4-11
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
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Identifying Users Transparently 5-5
Understanding Transparent User Identification 5-6
Rules and Guidelines for Transparent User Identification 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
Authentication Realms 5-11
External Authentication 5-11
Configuring External Authentication through an LDAP Server 5-11
Enabling RADIUS External Authentication 5-12
Creating an Active Directory Realm for Kerberos Authentication Scheme 5-12
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
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
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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 6-9
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
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
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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
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
URL Category Logging in Access Logs 9-20
Regular Expressions 9-20
Forming Regular Expressions 9-20
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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
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 10-11
Time Ranges and Volume Quotas 10-12
Volume Quota Calculations 10-12
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
How to Configure Identification of 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 HTTPS Traffic 11-1
Managing HTTPS Traffic through Decryption Policies Task Overview 11-2
Managing HTTPS Traffic through Decryption Policies BestPractices 11-2
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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 for the HTTPS Proxy 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
Adding Certificates to the Trusted List 11-10
Removing Certificates from the Trusted List 11-11
Routing HTTPS Traffic 11-11
Troubleshooting Decryption/HTTPS/Certificates 11-11
CHAPTER 12 Scan Outbound Traffic for Existing Infections 12-1
Overview of Scanning Outbound Traffic 12-1
User Experience When Requests Are Blocked by the DVS Engine 12-1
Understanding Upload Requests 12-2
Criteria for Group Membership 12-2
Matching Client Requests to Outbound Malware Scanning Policy Groups 12-2
Creating Outbound Malware Scanning Policies 12-3
Controlling Upload Requests 12-4
Logging of DVS Scanning 12-6
CHAPTER 13 Configuring Security Services 13-1
Overview of Configuring Security Services 13-1
Overview of Web Reputation Filters 13-2
Web Reputation Scores 13-2
Understanding How Web Reputation Filtering Works 13-2
Web Reputation in Access Policies 13-3
Web Reputation in Decryption Policies 13-4
Web Reputation in Cisco IronPort Data Security Policies 13-4
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