like routing and VPN. To see which mode your ASA is currently running, use the show mode command. Here you can see we're starting with our 5540 in single mode: ASA-5540# sho mode Security context mode: single To start, we'll need to put the ASA into multicontext mode with the mode command. This is a high-impact command that changes the default behavior of the switch. The ASA will warn you of this when you initiate the command: -5540 (config)# mode multiple WARNING: This command will change the behavior of the device WARNING: This command will initiate a Reboot Proceed with change mode? [confirm] Upon confirmation, we will be asked if we want to convert the system configuration. Once we commit, the ASA will reboot and initiate the process: Convert the system configuration? [confirm] The old running configuration file will be written to flash The admin context configuration will be written to flash The new running configuration file was written to flash Security context mode: multiple SHUTDOWN NOW Message to all terminals: change mode Rebooting When the ASA reboots, it may report a pile of errors. If the ASA already had a config- uration, many of those lines would likely fail, especially if any of them had to do now-unsupported features such as VPN, QoS, or routing. Additionally, configuration having to do with interfaces may fail, since these interfaces have not been allocated to a context yet. A quick check with the show mode command will confirm that our ASA 5540 has been converted: ASA-5540# sho mode Security context mode: multiple Chapter 28: ASA Firewall Configuration We now find ourselves in the system context. From here, we can manage all other contexts. Additionally, failover must be configured from the system context, as we'll see in the next section. Once the system has rebooted into multicontext mode, there will be one context preconfigured: ASA-5540# sho context Context Name Class Interfaces *admin default Managemento/o disko:/admin.cfg Total active Security Contexts: The admin context will have the fo