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NetBackup 6.0 Backup Process Flow

1. Upon startup, nbpem obtains all of the Backup Policy information via

2. nbproxy process from

3. bpdbm. The currently configured Backup Policy information is used to create the job worklist for all

scheduled jobs. The

build_worklist function runs only once when nbpem starts up. Once this information is obtained, the

nbpem worklist will beretained in memory. nbpem calculates when each job in the worklist is due to run and a timer is set to

the due time for each job

that needs be run. nbpem sets this timer for each job to track when the job is out of window. When the

job is due, the timer

expires and

4. nbpem issues a request to nbjm via pbx to schedule the backup using a job function of job start.

The nbpem service is a job

scheduler.

5. nbjm initiates a backup job by communicating with bpjobd and the job is added to the job list in the

jobs database. The job will

now be visible in the Activity Monitor. The job will initially be in a queued state, waiting for resources to

be allocated. bpjobdreceives both data and status for any internal job started by nbjm while external or foreign jobs handle

their own

communication with bpjobd. The nbjm service assigns, runs, executes, and starts jobs. If the job

remains queued and the out

of window timer expires, nbpem notifies nbjm to cancel the job. Normally, nbpem will wait for

notification from nbjm that

the job has either completed, or been cancelled. In either case, nbpem sets a timer in order to keep

track of when the job is due

next. Now that the job has been submitted to the job manager, nbjm, the checks for resources are

made. This involves the

NetBackup Resource Broker.

6. nbjm makes a request for resources to nbrb, the NetBackup resource broker, on the Enterprise MediaManager Server. The

NetBackup Resource Broker (nbrb) is another component of the Intelligent Resource Manager that runs

continuously on an

Enterprise Media Manager Server. nbrb uses the PBX process to communicate with other IRM and EMM

services.

7. The resource broker uses its associated nbproxy service to access resource consumption constraints

from bpdbm on the Master

Server.

8. This information includes configured policies and other attribute information such as max jobs per

policy, max jobs per client,

and max jobs this client. For a normal backup,

9. nbrb secures the physical resources from nbemm which can include storage units, tape drives, and

media ids.

10. Those resources are then marked as reserved in the EMM database. PBX is again used for this

communication.

11. nbrb will also request that EMM suspend avrd drive scanning on the assigned scan host.

12. Once the requested resources are acquired, nbrb notifies nbjm that resources have been allocated.

The job will remain in a

queued state until all of the resources are allocated for the job by nbrb. Once the resources necessary

for the job have been

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acquired from the Resource Broker, nbrb, the job can go active. nbjm will send a message to bpjobd,

activating the job in the

Activity Monitor.

13. When the job goes active, nbjm on the Master Server communicates with the Media Server via vnetd

to start bpbrm and pass

the start job arguments to that process.

14. bpbrm starts the actual backup by using the client daemon, vnetd, to start the backup and archiveprogram, bpbkar, on the

remote Client.

15. On the Media Server, the backup and restore manager, bpbrm, starts the appropriate media

manager process, bptm for tape and

bpdm for disk. The bptm process on the selected Media Server will SCSI reserve the drive(s) and then

16. issue a mount request to ltid.

17. ltid will forward the robotic mount request to tXXd. The tXXd process spawns a child, which issues a

drive unload and sends

the mount request to tXXcd. The tXXcd process spawns a child to issue the robotic move medium

command. The tXXd child

polls the drive, waiting for it to become ready and returns to ltid, which updates the mount statistics in

the EMM database andthen returns to bptm. The bptm process opens the drive path, positions and starts waiting for write

data. nbjm will

communicate the job status information to bpjobd as necessary and also accept job requests from

bpjobd such as; cancel,

restart, and resume.

18. The bpbkar program sends information about files within the image to the

19. backup and restore manager, which then communicates with

20. bpdbm in order to create image records in image database.

21. bpbkar transmits the backup image through vnetd to bptm or bpdm as directed.

22. The bptm or bpdm process forks a child process for this non-localized backup, which receives the

image and stores it block by

block into a shared memory segment.23. The original bptm process then takes the image from shared memory and directs it to the allocated

storage media. After all

Client data has been written,

24. bpbrm sends job completion information to nbjm via vnetd.

25. nbjm will send a message to bpjobd so that the Activity Monitor shows the job is now Done.

26. nbjm also triggers the release of resources for completed jobs, notifying nbrb by writing in the job

progress log.

27. nbjm will report the job exit status to nbpem who will then recalculate the next due time of the job.