As a network engineer, I try to avoid GUI configuration tools. Browsing through the CCNA Security book from Cisco Press, however, I was tempted to walk through the IPS configuration process demonstrated. I quickly configured the bare minimum on a router required to run SDM, and had the GUI up and running a minute later.
Unfortunately, when I went to click the IPS tab under the configuration portion of the utility, I met with an error message.
Your current Java memory heap size is less than 256 MB, the amount required for IOS IPS to run. To change the Java memory heap size, open the Java control panel and enter -Xmx256m in the Java Applet Runtime Settings dialog. This dialog is in the Java tab, or in the Advanced tab of the Java control panel. After you have changed the Java heap size, restart Cisco SDM. Click Help for more information.
It turns out this is a lie. SDM, at least the most recent version, actually requires more than 256 MB of Java heap space. I was successful after setting a limit of 512 MB. In an effort to save others the same trouble I had in the future, here's how to fix this on Windows 7:
- Open the Control Panel.
- Navigate to Programs, and open the Java control panel.
- Under the Java tab, in the Java Runtime Environment Settings pane, click View.
- For all enabled Java versions, enter -Xmx512m under Runtime Parameters.
- Hit OK and close the control panel.
Finally, close all instances of SDM (including any browser pages) and restart it. You should now be able to access the IDS/IPS interface in SDM.