AsyncOS 8.6 for Cisco Web Security Appliances User Guide

438 Pages·2015·4.04 MB·English

AsyncOS 8.6 for Cisco Web Security
Appliances User Guide
Published: March 3, 2015
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AsyncOS 8.6 for Cisco Web Security Appliances User Guide
© 2014-2015 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 8.6 1-2
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 1-5
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 2-26
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 2-31
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
Overview of Connect the Appliance to a Cloud Web Security Proxy 3-1
Cloud Connector versus Standard Mode 3-2
Documentation 3-4
Deployment 3-5
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: 3-6
Step 4. Set the Appliance Mode 3-6
Step 5. Configure Cloud Connector Settings 3-6
Step 6. Configure Network Interfaces and Wiring 3-7
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 3-10
Preventing Loss of Secure Data 3-10
Cloud Connector Logs 3-10
Subscribing to the Cloud Connector Logs 3-10
Identities 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
Credentials 5-2
Configuring Single-Sign-on 5-2
Tracking Credentials for Reuse During a Session 5-3
Authentication and Authorization Failures 5-3
Authentication Realms 5-3
External Authentication 5-3
Configuring External Authentication through an LDAP Server 5-4
Enabling RADIUS External Authentication 5-4
Creating an Active Directory Realm for Kerberos Authentication Scheme 5-4
Creating an Active Directory Authentication Realm 5-6
Creating an LDAP Authentication Realm 5-8
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About Deleting Authentication Realms 5-13
Configuring Global Authentication Settings 5-13
Authentication Sequences 5-18
About Authentication Sequences 5-19
Creating Authentication Sequences 5-19
Editing And Reordering Authentication Sequences 5-20
Deleting Authentication Sequences 5-20
Failed Authentication 5-20
About Failed Authentication 5-21
Bypassing Authentication 5-21
Permitting Unauthenticated Traffic While Authentication Service is Unavailable 5-21
Granting Guest Access After Failed Authentication 5-22
Define an Identity that Supports Guest Access 5-22
Use an Identity that Supports Guest Access in a Policy 5-22
Configure How Guest User Details are Logged 5-23
Failed Authorization: Allowing Re-Authentication with Different Credentials 5-23
About Allowing Re-Authentication with Different Credentials 5-23
Allowing Re-Authentication with Different Credentials 5-23
Tracking Identified Users 5-24
Supported Authentication Surrogates for Explicit Requests 5-24
Supported Authentication Surrogates for Transparent Requests 5-24
Tracking Re-Authenticated Users 5-24
Credentials 5-25
Credential Format 5-25
Credential Encryption for Basic Authentication 5-25
About Credential Encryption for Basic Authentication 5-25
Configuring Credential Encryption 5-26
Troubleshooting Authentication 5-26
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
Identity Criteria 6-2
Classifying Users and Client Software 6-3
Identities and Authentication 6-8
Troubleshooting Identities 6-9
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CHAPTER 7 SaaS Access Control 7-1
Overview of SaaS Access Control 7-1
Authenticate SaaS Users 7-2
Certificates and Keys 7-2
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 Classify URLs for Policy Application 8-1
Overview of Categorizing URL Transactions 8-1
Categorization of Failed URL Transactions 8-2
Enabling the Dynamic Content Analysis Engine 8-2
Uncategorized URLs 8-2
Matching URLs to URL Categories 8-3
Reporting Uncategorized and Misclassified URLs 8-3
URL Categories Database 8-3
Configuring the URL Filtering Engine 8-4
Managing Updates to the Set of URL Categories 8-4
Understanding the Impacts of URL Category Set Updates 8-5
Effects of URL Category Set Changes on Policy Group Membership 8-5
Effects of URL Category Set Updates on Filtering Actions in Policies 8-5
Merged Categories - Examples 8-6
Controlling Updates to the URL Category Set 8-7
Manually Updating the URL Category Set 8-7
Default Settings for New and Changed Categories 8-8
Verifying Existing Settings and/or Making Changes 8-8
Receiving Alerts About Category and Policy Changes 8-8
Responding to Alerts about URL Category Set Updates 8-8
Filtering Transactions Using URL Categories 8-9
Configuring URL Filters for Access Policy Groups 8-9
Configuring URL Filters for Decryption Policy Groups 8-11
Configuring URL Filters for Data Security Policy Groups 8-12
Creating and Editing Custom URL Categories 8-13
Filtering Adult Content 8-15
Enforcing Safe Searches and Site Content Ratings 8-15
Logging Adult Content Access 8-16
Redirecting Traffic in the Access Policies 8-17
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Logging and Reporting 8-17
Warning Users and Allowing Them to Continue 8-17
Configuring Settings for the End-User Filtering Warning Page 8-18
Creating Time Based URL Filters 8-19
Viewing URL Filtering Activity 8-19
Understanding Unfiltered and Uncategorized Data 8-19
Access Log File 8-20
Regular Expressions 8-20
Forming Regular Expressions 8-20
Guidelines for Avoiding Validation Failures 8-21
Regular Expression Character Table 8-22
URL Category Descriptions 8-23
CHAPTER 9 Create Policies to Control Internet Requests 9-1
Overview of Policies: Control Intercepted Internet Requests 9-1
Managing Web Requests Through Policies Task Overview 9-2
Managing Web Requests Through Policies Best Practices 9-2
Policies 9-2
Policy Types 9-3
Policy Order 9-5
Creating a Policy 9-5
Policy Configuration 9-6
Block, Allow, or Redirect Transaction Requests 9-7
Client Applications 9-7
About Client Applications 9-7
Using Client Applications in Policies 9-8
Exempting Client Applications from Authentication 9-9
Time Ranges and Quotas 9-9
Volume Quota Calculations 9-10
Time Quota Calculations 9-10
Access Control by URL Category 9-10
Creating Custom URL Categories 9-11
Using URL Categories to Identify Web Requests 9-12
Using URL Categories to Action Web Request 9-12
Remote Users 9-13
About Remote Users 9-13
Configuring Identification for Remote Users 9-14
Configuring Identification of Remote Users 9-14
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Display Remote User Status and Statistics for ASAs 9-15
Troubleshooting Policies 9-15
CHAPTER 10 Create Decryption Policies to Control HTTPSTraffic 10-1
Overview of Create Decryption Policies to Control HTTP Traffic 10-1
Managing HTTPS Traffic through Decryption Policies Task Overview 10-2
Managing HTTPS Traffic through Decryption Policies BestPractices 10-2
Decryption Policies 10-2
Enabling the HTTPS Proxy 10-3
Controlling HTTPS Traffic 10-4
Configuring Decryption Options 10-4
Authentication and HTTPS Connections 10-5
Root Certificates 10-5
Managing Certificate Validation and Decryption for HTTPS 10-6
Valid Certificates 10-6
Invalid Certificate Handling 10-6
Uploading a Root Certificate and Key 10-7
Generating a Certificate and Key 10-7
Configuring Invalid Certificate Handling 10-8
Options for Certificate Revocation Status Checking 10-9
Enabling Real-Time Revocation Status Checking 10-9
Trusted Root Certificates 10-10
Adding Certificates to the Trusted List 10-10
Removing Certificates from the Trusted List 10-11
Routing HTTPS Traffic 10-11
Troubleshooting Decryption/HTTPS/Certificates 10-11
CHAPTER 11 Scan Outbound Traffic for Existing Infections 11-1
Overview of Scanning Outbound Traffic 11-1
User Experience with Blocked Requests 11-1
Understanding Upload Requests 11-2
Criteria for Group Membership 11-2
Matching Client Requests to Outbound Malware Scanning Policy Groups 11-2
Creating Outbound Malware Scanning Policies 11-3
Controlling Upload Requests 11-4
Logging 11-6
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