Re: training for new DBA's
- From: Jeff C <backseatdba@xxxxxxxxx>
- To: oracle@xxxxxxxxxxx
- Date: Mon, 17 Feb 2014 07:42:08 -0800
Do you have them backup all the datafiles before starting recovery? If you
have a 500g database that will take a long while?
On Tue, Feb 11, 2014 at 9:13 AM, Dave Morgan <oracle@xxxxxxxxxxx> wrote:
> Communication is a wonderful thing. Too bad I am so poor at it :(
>
> From: Mark Bobak <Mark.Bobak@xxxxxxxxxxxx>
>> Date: Mon, 10 Feb 2014 19:47:05 +0000
>>
>> ³ŠBack up the redo logsŠ²
>>
>
> The database in question has a corrupt data file, other than that it is
> complete
> and is sitting on disk. When I say backup the online redo, I mean copy the
> redo and datafiles as Hans has mentioned. If a recovery goes bad:
>
> How do you return to where you started if you do not have a copy of where
> you started.
>
> Second, anyone can learn skills and technique, however, we have found that
> you cannot
> teach the correct attitude/mindset/paranoia. Either the candidate has it
> or they do not.
>
> Date: Mon, 10 Feb 2014 11:09:57 -0600
>> From: Chris Taylor <christopherdtaylor1994@xxxxxxxxx>
>>
>>
>> For this test that always fails, do you specify the Recovery Time
>> Objective
>> (RTO) - is it clear to these juniors what "success" is? I'm assuming it
>> is
>>
>
> Success is not defined by recovery. It is defined by whether you took a
> copy of the
> corrupt database before you started or not. The candidate DOES NOT know
> this. The
> recovery is a difficult one. When I first ran into it 12 years ago it took
> 4 attempts
> to get it right.
>
>
> well defined, but I have a hard time with tests that are setup to fail.
>> Juniors are going to make mistakes - that's why they are juniors and not
>> intermediaries or seniors. Do they have access to a senior level during
>> this test to gauge their input and is that input freely given?
>>
>
> They have had all the support they want or need for 3 months. If they do
> not have the
> correct attitude they are of no use to us.
>
> Remember I am not testing skills or abilities.
>
>
> I could see sacking a junior for not engaging with team members to make
>> sure they had
>> their bases covered, but not for solely failing to backup redo logs in a
>>
>
> So, do I place a candidate who does not follow procedures in a client
> environment?
> They are not juniors yet, they are candidates.
>
>
> final test that even some intermediaries (and maybe a few seniors) would
>> fail.
>>
>
> Our definitions of intermediates and seniors are different then.
>
>
>
> (Granted, I'm probably reading more into your comment than intended
>
>> and I sincerely apologize if so - I'm just genuinely puzzled by what you
>> posted and I'm sure there's more to it than what you provided - at least I
>> hope so)
>>
>
> See first line :)
>
>
> Date: Mon, 10 Feb 2014 14:56:14 -0700
>> From: Hans Forbrich <fuzzy.graybeard@xxxxxxxxx>
>>
>>
>> a) Never Back up the Redo Logs, and
>> b) Before starting a recovery, they will take a safety COPY (but not
>> back up) of the existing Redo Logs so they can restart a recovery if
>> they botch the steps.
>>
>>
> Amen
> <tease>
> Can you do that in OEM :)
> </tease>
>
>
> I then go on to highlight some cases, and emphasize that more DBAs have
>> been fired for violating these two points than any other reason (of
>> which I am aware). 9 Well, they were not fired for violating the points,
>> but for getting the recovery into an unmanageable and unrecoverable
>> state, and having no plan B since they overwrote their Redo Logs with
>> old copies.
>>
>
> Exactly
>
>
> With other teams "knowing better than the DBA" about what backups are
>> required thus avoiding RMAN, and doing things like BCV splits and
>> shoosting the mirror off to tape, it is highly likely that a) gets
>> violated at some point.
>>
>
> Actually, if the two teams co-operate the use of silvering and mirroring
> (aka BCV, SRDF, etc) is just as safe. IF YOU HAVE THE CORRECT LEVEL OF
> PARANOIA!
>
>
>
>> A Safety Copy in b) is tucked away in the DBA's home directory or some
>> other non-traditional place;
>> That Safety Copy should not be used, or required, unless the world has
>> gone TU
>>
>
> Amen
>
>
>
> John Hallas wrote:
>
> If you are going through that number of trainees and your success rate is
>> only 40% then I seriously wonder how good your training is.
>> You are investing 3 months of effort and then throwing 60% of it away.
>> Perhaps it is better to look at your methods and trainers than just
>> saying "Bye, Bye"
>>
>
> Actually what we need is a way to determine if the candidate has the
> correct attitude in the first week.
> That would improve our ROI immensely.
>
>
> Donald Freeman wrote:
>
> I don't know. If you have very high standards and very serious
>> consequences (think "Top Gun" or "Fukushima") then I can see washing out
>> 60%.
>> If your business model supports that then fine. It doesn't take a very
>> big incident to cost millions. I don't know anybody personally whose
>> salary would offset a big mistake.
>>
>
> The loss of a client's database would pretty well ruin our consultancy.
> No-one would trust us. Apart from the
> fact that placing a DBA without the correct attitude could open us to a
> charge of incompetence and/or negligence.
>
> Apart form the fact how do I sit in front of a 15 year client and tell
> them "Although you only pay us do two things we are incapable of doing that"
> The 2 things being protect the data from loss and provide access to the
> data.
>
>
>
> Fair shout Donald and I don't want to get too bogged down into the
>> original poster's situation.
>> However a 60% failure rate does seem high after 3 months training. How
>> many on this list, who consider themselves
>> good/competent/reasonable DBAs would fail the same test. Is it the test ,
>> the training, the selection process? I don't know but it seems a flawed
>> process to me.
>>
>
> Every good/competant/reasonable DBA could do the recovery. However, I
> doubt anyone, no matter their skill, would be successful the first time,
> unless you got very lucky. However, as mentioned, the recovery is not what
> you are judged on!
>
> HTH
>
> Dave
>
>
> --
> Dave Morgan
> Senior Consultant, 1001111 Alberta Limited
> dave.morgan@xxxxxxxxxxx
> 403 399 2442
> --
> //www.freelists.org/webpage/oracle-l
>
>
>
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