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I think that date (Jan 18, 2038) is the limit of the unix signed-integer
32-bit clock. It's been a while since I've done the math but that's the
right range.
All time in Unix is kept as a 32-bit signed integer as the number of seconds
since Jan 1, 1970. Technically, therefore, there's a time in the future
when the unix clock will rollover and be useless. Also, most probably,
we'll all be on 64-bit or better OS's by then and this'll never be an issue.
Still, I think netbackup is calculating the date as 0x7FFFFFFF offset from
the base time and that's as close to infinity as will be allowed by their
expiration method.
As to the other, I think the tape expiration date is set to the date of the
last-to-expire image on that tape. Read the "recalculate" option on the
bpexpdate man page for more.
-Mark
-----Original Message-----
From: Dongfang Liao [mailto:dongfang.liao AT rogers DOT com]
Sent: Wednesday, March 27, 2002 8:03 PM
To: veritas-bu
Subject: [Veritas-bu] how does NBU find out if hte image has been expired or
not?
Hi All,
Have you seen this kind of problem before? can anyone tell me how NBU finds
out if hte image has been expired or not?
We just found out some one years old image files, which the expiration dates
have been changed manually to 2 years old after they were backed up, were
lost without any reason. We suspect NBU bpdbm mis-thinks the images have
been expired and cleans up these image files since we found out the
retention level of the image files were not changed after we compared some
image files that we manually change the expiration date. The only changes is
the expiration date of the images.
Will it be possible that bpdbm clean up the images files just by the
retention level without checking the expiration date? or will NBU bpdbm
check the both retention level and expiration date?
By the way, The retention level 9, which is supposed to be infinity, By in
my environment, the expiration date for "infinity" is set to "Mon Jan 18
22:14:07 2038". Make sense? But if you change your image to retention level
9, and check the expiration date on the image file, you will get this date.
Appreciate for any help!
-----------------------
Thanks
ldf
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<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff size=2>I
think that date (Jan 18, 2038) is the limit of the unix signed-integer 32-bit
clock. It's been a while since I've done the math but that's the right
range.</FONT></SPAN></DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff size=2>All
time in Unix is kept as a 32-bit signed integer as the number of seconds since
Jan 1, 1970. Technically, therefore, there's a time in the future when
the
unix clock will rollover and be useless. Also, most probably, we'll all
be
on 64-bit or better OS's by then and this'll never be an
issue.</FONT></SPAN></DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff
size=2>Still,
I think netbackup is calculating the date as 0x7FFFFFFF offset from the base
time and that's as close to infinity as will be allowed by their expiration
method.</FONT></SPAN></DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff size=2>As to
the other, I think the tape expiration date is set to the date of the
last-to-expire image on that tape. Read the "recalculate" option on the
bpexpdate man page for more.</FONT></SPAN></DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff
size=2>-Mark</FONT></SPAN></DIV>
<DIV><SPAN class=520143716-28032002><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=520143716-28032002></SPAN><FONT face=Tahoma><FONT size=2><SPAN
class=520143716-28032002><FONT face=Arial
color=#0000ff> </FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=Tahoma><FONT size=2><SPAN
class=520143716-28032002> </SPAN>-----Original
Message-----<BR><B>From:</B>
Dongfang Liao [mailto:dongfang.liao AT rogers DOT com]<BR><B>Sent:</B>
Wednesday, March
27, 2002 8:03 PM<BR><B>To:</B> veritas-bu<BR><B>Subject:</B> [Veritas-bu] how
does NBU find out if hte image has been expired or
not?<BR><BR></DIV></FONT></FONT>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV><FONT face="Lucida Console" size=2>Hi All,</FONT></DIV>
<DIV><FONT face="Lucida Console" size=2></FONT> </DIV>
<DIV><FONT face="Lucida Console" size=2>Have you seen this kind of problem
before? can anyone tell me how NBU finds out if hte image has been expired or
not?</FONT></DIV>
<DIV><FONT face="Lucida Console" size=2></FONT> </DIV>
<DIV><FONT face="Lucida Console" size=2>We just found out some one years
old image files, which the expiration dates have been changed manually
to
2 years old after they were backed up, were lost without any reason. We
suspect NBU bpdbm mis-thinks the images have been expired and cleans up these
image files since we found out the retention level of the image files were
not
changed after we compared some image files that we manually change the
expiration date. The only changes is the expiration date of the images.
</FONT></DIV>
<DIV><FONT face="Lucida Console" size=2></FONT> </DIV>
<DIV><FONT face="Lucida Console" size=2>Will it be possible that bpdbm clean
up the images files just by the retention level without checking the
expiration date? or will NBU bpdbm check the both retention level and
expiration date?</FONT></DIV>
<DIV><FONT face="Lucida Console" size=2></FONT> </DIV>
<DIV><FONT size=2><FONT face="Lucida Console">By the way, <FONT
color=#000080>The retention level 9, which is supposed to be infinity, By in
my environment, the expiration date for "infinity" is set to "Mon Jan 18
22:14:07 2038". Make sense? But if you change your image to retention level
9,
and check the expiration date on the image file, you will get this
date.</FONT></FONT></FONT></DIV>
<DIV><FONT face="Lucida Console" size=2></FONT> </DIV>
<DIV><FONT face="Lucida Console" size=2>Appreciate for any help!</FONT></DIV>
<DIV><FONT face="Lucida Console"
size=2>-----------------------<BR>Thanks<BR>ldf</FONT></DIV></BLOCKQUOTE></BODY></HTML>
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