I bought a new Cisco ASA5505-SEC-BUN-K9 firewall which support up to 25 users. Do I need to upgrade both the ASA version and the ASDM in order to restore my config? What effect will the upgrade have?
ASA is the firmware of the Cisco Firewall
ASDM is the device manager (GUI) to configure it
If you are using ASDM to manage your firewall you will need to update it to the version coupled with ASA e.g. "ASA 9.2(1)/ASDM 7.2(1)".
For the other part I suggest reading the changelog of the release you are going to use.
Managing Feature Licenses for Cisco ASA 5500 Version 8.1
A license specifies the options that are enabled on a given security appliance. It is represented by an activation key which is a 160-bit (5 32-bit words or 20 bytes) value. This value encodes the serial number (an 11 character string) and the enabled features.
This document describes how to obtain an activation key and activate it. It also describes the available licenses for each model. This document includes the following sections:
•Supported Feature Licenses on the ASA 5580
•Information About Feature Licenses
•Guidelines and Limitations
•Viewing Your Current License
•Obtaining an Activation Key
•Entering a New Activation Key
•Upgrading the License for a Failover Pair
•Feature History for Licensing
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