[CentOS] Is ext4 safe for a production server?
listmember at greenspot.fi
Fri Dec 11 14:52:23 UTC 2009
Centos 5.x, ext3, md raid1
As I do not have UPS for all machines, and I most often use md raid
(level 1), I would like to turn the write cache off for all of my server
discs. But how?
Below is what I have already found out:
On the page
I read that I could do this by running
hdparm -W0 /dev/sdX
, but when I say
it says that the -W option is “dangerous”.
This is the current hdparm output for one of my raid discs:
[root at mail etc]# hdparm /dev/sda
IO_support = 0 (default 16-bit)
readonly = 0 (off)
readahead = 256 (on)
geometry = 38913/255/63, sectors = 625142448, start = 0
(BTW, here is a hdparm tutorial for Ubuntu:
And when I get this done, then how can I make the setting last over the
P.S. Do you really have to quote the whole thread when you respond?
Jussi Hirvi * Green Spot
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jussi.hirvi at greenspot.fi * http://www.greenspot.fi
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