9.0 observations
rank1seeker at gmail.com
rank1seeker at gmail.com
Tue Feb 14 17:18:39 UTC 2012
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OpenSSH:
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After taking advantage of new 'KexAlgorithms'
# sshd -T | grep KexAlgorithms
will never show it ...
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WiFi:
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'media OFDM/54Mbps' breaks setup (supplied to 'ifconfig wlan0').
'ucastrate' and 'mcastrate' will set it instead.
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gpart
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On a MD vnode bassed image, of size:
1g or 2g:
# gpart create -s MBR md0
Will create starting offset at 63 sector
=> 63 2097089 md0 MBR (1.0G)
=> 63 4194241 md0 MBR (2.0G)
1432m:
# gpart create -s MBR md0
Will create starting offset at 33 sector
=> 33 2932703 md0 MBR (1.4G)
NOW, looking at this new interesting alignment flag (-a 4k) ...
I started to add slices with it and taking into consideration BOTH above cases, all it really does under MBR, is it takes INITIAL offset and simply STAMPS it between slices, making NONE to align(nor to offset, nor to size => mess!):
1g or 2g:
63 63 - free - (31k)
1432m:
33 33 - free - (16k)
However, with GPT, all is stable:
# gpart create ... always sets offset to 34, regardless of img size
And (-a 4k) properly modifies BOTH slice's 'offset' and 'size', to be divisable with 8, without residue(=0)
In case:
--
# gpart show -p md0
=> 34 2932669 md0 GPT (1.4G)
34 1024 md0p1 freebsd-boot (512k)
1058 6 - free - (3.0k)
1064 501760 md0p2 freebsd-ufs (245M)
--
6 sectors were added in favor of aligning md0p2's offset
Here I have a question. Is it true that FIRST slice, should always start at 1Mb offset (-b 1M) and why?
Should I use (-b 1M) for first and (-a 4k) for all other added slices?
Finally, taking into consideration first MBR alignment issues.
How should one proceed if he wants to put MBR on 4k sector disk?
Domagoj Smolčić
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