I find that I have gotten confused on all the different commands I can use as an admin to discover what might be wrong with my MongoDB cluster. For example, running the split command, I got an error that "pre-condition failed". I found the part of the code related to its error message, 13105, https://github.com/mongodb/mongo/blob/master/src/mongo/client/syncclusterconnection.cpp#L219 , but I'm still confused on what I am seeing.
So I wanted to systematically check every part of my cluster. These are the commands I have run and remember right off the bat, but I'm pretty sure I'm forgetting some! I was never a DBA before looking at Mongo, so it would really help me to have a debugging checklist of info to get.
So my question is, have I got all the commands I need to , to get the status and configuration of each aspect of my cluster from a Mongo Console? For example, I feel sure I was able to see the sizes of each shard chunk used, but I didn't get that yet. thank you!
Update 2014-11-22, modified the list below to include my summary findings and @wdberkeley's answer.
//TIPS For MongoDB Debugging //1.Get General info on configs passed and the IP's (in Bash) ps aux | grep -in mongo //1A.Alternatively, to see details of configs on a single server use admin db.serverCmdLineOpts() //2.Shard chunk/ranges status (from the mongoS balancer node) sh.status() //2A.Shard Status, verbose output sh.status(true) //3.Replica Set Status (from a replica set node, NOT from a mongoS) rs.status() //4.Mongo Server info (from anywhere; VERY LONG output) db.serverStatus() //5.Log summary from configured file or copy/paste of system.output into a .log file (from Bash) mloginfo myCapturedLogs.log --distinct //6.Diagnostic tools (from Bash) mongostat mongotop //7.Check Q&A / Reference sites. Refs;  The amazing mtools includes log parsing and log timeline visualization. https://github.com/rueckstiess/mtools  Q&A / Reference sites' URLS; 7A.mongo Shell Quick Reference http://docs.mongodb.org/manual/reference/mongo-shell/ ; 7B.StackOverflow; 7C.The stackexchange solely for dba questions, eg http://dba.stackexchange.com/questions/48232/mongodb-config-servers-not-in-sync ; 8.Mongo Diagnostics FAQ http://docs.mongodb.org/manual/faq/diagnostics/#faq-memory