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Vickie's avatar
Vickie
Level 6
12 years ago
Solved

How Netbackup Command works

Dear experts,
 
I have a query & concern regarding the COMMAND we use in NETBACKUP.
I wonder & doubt as from where and how these COMMANDS get the output, 
Lets take an eg,
 
Command,
./bppllist ( will give list of policy ). 
How it get the list, first where it will go or hit to get policy name. 
What is the exact route or way it'll follow to give the output.
Whom it'll ask or query for the list.
 
 
Same query is for every COMMAND we use in NETBACKUP,
bpplclients,

bpplinfo,

bpclient,

bpimagelist,

vmquery.

vmupdate, and many more....
 
Please assist me, if this is possible we get the way as how command works.
 
 
 
  • In 7.5 most information comes from the NBDB database. Policy info still comes from flat files, and part of the catalog db comes from the .f files (binaries, but is converted). There is little chance of finding documentaion on the exact path each command uses : 1. It doesn't exist, well not for every command 2. Even Tech Support doesn't have this (we have to work it out ourselves ) 3. Generally, you don't need to know the exact path they take Generally, Commands in volmgr/bin get their info from EMM (apart from scsi_command and scan) nbemmcmd command from emm db bplist/ bpflist from .f files in catalog bpimmedia / bpmedialist /bpimage from EMM nbstlutil from EMM That covers most of the day to day stuff I think. If you want to find out exactly how : 1. Turn on all the logs (yep, every single one) 2. Run a command, check which logs changed 3. Uses these logs, find the lines and put them in time order 4. Delete the lines that aren't relevant You have the answer ... There is a big problem with this ... Some logs update constantly, even when the system is idle. (EMM / bpdbm / nbrb / nbstserv to name a few) Therefore when you run a command (eg. nbemmcmd -some options) some of the lines in EMM will be due to the command, but some will be due to it just doing it's normal day-to-day things. It can be worked out, by finding the PID/ TID, but then again, EMM is multi threaded and so even these can change. Some commands jump from log to log - for example, many command in netbackup/bin/admincmd start with entries in the admin log, but this might go out and make a connection via PBX to another process, which logs in another log, but then again, the connection might go via vnetd, or perhaps nbproxy gets involved ... you can bgin to see the problem. How do I do it, well a combination of the above generally - I have a script that will tell me what legacy logs change when I run a command which helps, but is in no way the complete answer. Depending on what I'm tracing (and it's usually some job, so multiple processes / commands involved) it can take hours, and if I make a mistake, or miss something, I have to start again. There are flowcharts (trouble shooting guide) that show how some things work (eg. backups / restores) and there are some TNs / Internal only documentaion for others but not everything is covered. It's pretty much impossible to work out every command, and even if you did, as soon as a new version of NBU is released you can be pretty sure something somewhere changed, so youd have to start again. I, and I suspect my colleagues work on a need to know basis. If we need that level of detail, we work it out. Generally with experience, you have at least an approimate idea, and very often this is sufficient. You would be much much better off spending your time doing the following. Learning how to collect the logs requested by tech support (many people can't do this). Learning how to narrow down an issue through testing Learning when to recognise that NBU probably isn't the cause, or the main cause (hint, network issues and drive/ library issues) Troubleshooting techniques > start with the most likely cause first (yes you might be wrong, but on 'average' this is a winning approach) Understanding that when you find a problem that might be the cause of the symptoms, this HAS to be eliminated before further troubleshooting takes place. Knowing the importance of setting the PATHS for NBU commands in the OS PATH variable Martin