Check_MK Werk 1622: megaraid_bbu: handle case isSOHGood and consider it as critical

ID: 1622 Title: megaraid_bbu: handle case isSOHGood and consider it as critical Component: Checks & Agents Level: 1 Class: Bug Fix Version: 1.2.5i7 Thanks to Jukka Santala, who wrote: "Discovered (the hard way) that when MegaRAID BBU batteries degrade too low, disabling WriteBack cache, the firmware doesn't turn on "battery pack needs replacing" flag. Instead <tt>isSOHGood</tt> seems to be only reliable way to detect this condition. In this patch I've ranked it as critical, as it is fairly equivalent to battery pack missing. Unfortunately it's generally too late when this goes on, so it would be nice to have little warning. The current agents do not query "Absolute State of charge" off the controller, and on the DELL 12G RAID-controllers this statistics doesn't even exist; they also have different design capacity. Because of these limitations I've resolved to just listing the "Full Charge Capacity" in the check status. I considered having the passed on perfdata for graphing, but as they're only updated on battery re-learn, it's limited usability. This patch is against latest innovation versions, and has been tested again various DELL 9G, 11G and 12G servers with 5/i, 6/i, H700 and H710P RAID-controllers."