C H A P T E R
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Cisco ASA Series CLI Configuration Guide
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Setting General VPN Parameters
The ASA implementation of virtual private networking includes useful features that do not fit neatly into
categories. This chapter describes some of these features. It includes the following sections:
•
Configuring VPNs in Single, Routed Mode, page 1-1
•
Configuring IPsec to Bypass ACLs, page 1-1
•
Permitting Intra-Interface Traffic (Hairpinning), page 1-2
•
Setting Maximum Active IPsec or SSL VPN Sessions, page 1-3
•
Using Client Update to Ensure Acceptable IPsec Client Revision Levels, page 1-4
•
Implementing NAT-Assigned IP to Public IP Connection, page 1-6
•
Configuring Load Balancing, page 1-12
•
Configuring VPN Session Limits, page 1-17
•
Configuring the Pool of Cryptographic Cores, page 1-19
Note
SSL VPN in this chapter refers to the SSL VPN client (AnyConnect 2.x or its predecessor, SVC 1.x),
unless clientless (browser-based) SSL VPN is specified.
Configuring VPNs in Single, Routed Mode
VPNs work only in single, routed mode. VPN functionality is unavailable in configurations that include
either security contexts, also referred to as multimode firewall, or Active/Active stateful failover.
The exception to this caveat is that you can configure and use one connection for administrative purposes
to (not through) the ASA in transparent mode.
Configuring IPsec to Bypass ACLs
To permit any packets that come from an IPsec tunnel without checking ACLs for the source and
destination interfaces, enter the
sysopt connection permit-vpn
command in global configuration mode.
You might want to bypass interface ACLs for IPsec traffic if you use a separate VPN concentrator behind
the ASA and want to maximize the ASA performance. Typically, you create an ACL that permits IPsec
packets by using the
access-list
command and apply it to the source interface. Using an ACL is more
secure because you can specify the exact traffic you want to allow through the ASA.
Summary of Contents for 5505 - ASA Firewall Edition Bundle
Page 28: ...Glossary GL 24 Cisco ASA Series CLI Configuration Guide ...
Page 61: ...P A R T 1 Getting Started with the ASA ...
Page 62: ......
Page 219: ...P A R T 2 Configuring High Availability and Scalability ...
Page 220: ......
Page 403: ...P A R T 2 Configuring Interfaces ...
Page 404: ......
Page 499: ...P A R T 2 Configuring Basic Settings ...
Page 500: ......
Page 533: ...P A R T 2 Configuring Objects and Access Lists ...
Page 534: ......
Page 601: ...P A R T 2 Configuring IP Routing ...
Page 602: ......
Page 745: ...P A R T 2 Configuring Network Address Translation ...
Page 746: ......
Page 845: ...P A R T 2 Configuring AAA Servers and the Local Database ...
Page 846: ......
Page 981: ...P A R T 2 Configuring Access Control ...
Page 982: ......
Page 1061: ...P A R T 2 Configuring Service Policies Using the Modular Policy Framework ...
Page 1062: ......
Page 1093: ...P A R T 2 Configuring Application Inspection ...
Page 1094: ......
Page 1191: ...P A R T 2 Configuring Unified Communications ...
Page 1192: ......
Page 1333: ...P A R T 2 Configuring Connection Settings and QoS ...
Page 1334: ......
Page 1379: ...P A R T 2 Configuring Advanced Network Protection ...
Page 1380: ......
Page 1475: ...P A R T 2 Configuring Modules ...
Page 1476: ......
Page 1549: ...P A R T 2 Configuring VPN ...
Page 1550: ......
Page 1965: ...P A R T 2 Configuring Logging SNMP and Smart Call Home ...
Page 1966: ......
Page 2059: ...P A R T 2 System Administration ...
Page 2060: ......
Page 2098: ...1 8 Cisco ASA Series CLI Configuration Guide Chapter 1 Troubleshooting Viewing the Coredump ...
Page 2099: ...P A R T 2 Reference ...
Page 2100: ......