Re: Cron management...
Date: Wed, 22 Apr 2015 07:54:53 -0600
Message-ID: <5537A82D.6040800_at_gmail.com>
On 22/04/2015 6:25 AM, Mladen Gogala (Redacted sender mgogala_at_yahoo.com for DMARC) wrote:
> On 04/22/2015 03:18 AM, Freek D'Hooge wrote:
>> Mladen,
>> Ram,
>>
>> The data will stream between the database server and the media
>> server, regardless if you start rman from that server or from a "client".
>> On the db server the server processes will handover the data stream
>> to the NB library, which sends it to the configured media server.
>>
>>
>> regards,
>>
>> Freek
>>
>
> How will that happen if the library that facilitates that streaming
> (MML) is on the 3rd node? The communication primitives are in the
> library which resides on the 3rd node and can not be used from the DB
> server itself. It's rman executable which maps the library when the
> channel of type SBT is allocated, not the database. My understanding
> of that "solution" was that the plan was to have rman and MML on an
> independent node and connect to databases, according to schedule.
>
From the docs: "An RMAN channel represents one stream of data to a device, and corresponds to one database server session." More in depth at http://docs.oracle.com/database/121/BRADV/rcmtunin.htm#BRADV170 discusses the processes involved in reading and writing.
I agree with Freek - the channel is on the database machine. It is a server process and effectively does a form of 'direct path IO' with the database. At least some portion of the MML must be on the DB server machine.
That said, it is possible for the channel to communicate across the network with remote tapes and remote media software - such as Oracle's Secure Backup, which acts as an MML. This is discussed in the in-depth section of the docs - although there are large gaps in the details.
/Hans
-- http://www.freelists.org/webpage/oracle-lReceived on Wed Apr 22 2015 - 15:54:53 CEST