[Info-vax] The (now lost) future of Alpha.

[Jan-Erik Söderholm]

Den 2018-08-26 kl. 14:08, skrev Johnny Billquist:
> On 2018-08-25 17:43, Bill Gunshannon wrote:
>> On 08/25/2018 06:34 AM, Johnny Billquist wrote:
>>> On 2018-08-19 15:31, Bill Gunshannon wrote:
>>>> At the University we used tapes until it reached the point where a full
>>>> backup or restore would take more than 12 hours.  At that point we moved
>>>> to mirrored disks including one remote.
>>>
>>> Which is fine, until you want to recover that file that was deleted a 
>>> while ago, at which point you realize that mirrored disks are not the 
>>> same thing as backups... Two different solutions, to two different 
>>> problems.
>>>
>>>    Johnny
>>>
>>
>> They are when you take one set out of service at regular intervals
>> (like monthly) and store them away.  Disk drives are cheap.
>>
>> For most people tapes aren't much good either as:
>> a) they never get tested
>> b) depending on the kind of tape they are not really reliable
>> c) as technology changes you find yourself having to keep a
>>     lot of old hardware around just in case you need to read
>>     one of those tapes.
>> d) after keeping the old hardware around you find, when you
>>     need it, the drive:
>>                         <a> no longer works
>>                         <b> is not supported on any of your
>>                             current hardware
>>
>> Need I go on?   :-)
> 
> None of your points are really relevant. Mirroring still solves a different 
> problem than backups. And just one backup per month is a bit too seldom to 
> really be that useful.
> 
> But, to get back to tapes - funnily enough, tapes have been declared dead 
> so many times, and yet they still get used, even in new data centers... Go 
> figure.
> 
> But yes, the points you mention certainly are relevant. But in a way, that 
> is just a repeat of the same old story of people who don't do things 
> properly are bound to loose.
> 
>    Johnny
> 

There are also completely new ways to backup VMS systems.

We use ABC (Archive/Backup Client) for IBM TSM/Tivoli to
backup all disks. A file that was deleted from the live systems
is marked "inactive" for 60 days (configurable) before final
deletion. Restore of a file (active or inactive) is done in
seconds.

ABC stores all device parameters so that it can perform an
"image restore" of a full disk including init. And all three
systems has access to the other systems backups so a restore
of individual files or a full image restore can be done using
one of the other systems.

We are very happy with this solution that replaced the old one
where tapes were swapped in DLT drives...

Jan-Erik