LM-Series Console Server: ROMmon Recovery
Automated ROMmon Recovery Gets Your Network Back Up and Running
The recovery timeline. The LM-Series console server can automatically detect and recover a Cisco router in ROMmon mode in about the time it would take to get a cup of coffee.
Whether it’s a corrupted bit in the flash memory or an obscure virtual config setting or a break sequence that throws your Cisco router into ROMmon mode, the LM-Series can get your network back up and running automatically.
The ROMmon recovery feature starts with monitoring. The LM-Series is constantly polling managed devices and parsing the results every 30 seconds by default over the serial console connection. That means it’s not adding to production network traffic or slowing down the device from doing its primary job. When a router drops into ROMmon mode, it will be detected because the LM is looking for the hostname prompt every time a command is run. If it’s not there, or if it has reverted to the default Router, the LM will know something is wrong.
When a managed device is detected booting into ROMmon mode, the LM can automatically restart the device and break into the boot cycle, acting as a TFTP server to reload the previous configurations over a previously-configured IP connection. If a dedicated Ethernet connection or shared management network connection is not available, the LM can even push the data over the serial connection using X-modem, but it will take longer.
Up to 20 different running configs and six IOS images are stored automatically and locally on the LM for each managed device.
With the recovered image uploaded and decompressed, the LM will restart the device to load the previous configurations. The router will boot back up and continue operating. That’s ROMmon recovery that doesn’t require you to travel to the device and connect your laptop, saving you time and frustration.
Of course, these automatic processes can include alerts either in-band or out-of-band to notify you directly or through your centralized management tools exactly what’s going on.