Gentoo Archives: gentoo-user

From: James <wireless@×××××××××××.com>
To: gentoo-user@l.g.o
Subject: [gentoo-user] ZFS formating
Date: Fri, 01 Nov 2013 13:49:05
Message-Id: loom.20131101T140820-143@post.gmane.org
1 Hello,
2
3 >
4 So after readaing quite a bit about ZFS, I still have some simple
5 question(s). Can you install ZFS on a single drive? Does that make sense
6 or is it "illogical/dumb" to do so?
7
8
9 Is the latest version of SystemRescue the best media to use to format
10 disks with ZFS? Caveats?
11
12
13 Last, after looking at the thread from 17Sep2013, I have culled.
14 These bookmarks as the best resources to follow (any others?) :
15
16 http://wiki.gentoo.org/wiki/ZFS
17
18 Just emerge zfs and its depndancies. Special/additional Flags
19 recommended but not in the aforementioned resource listing?
20
21 turn off readahead. ZFS' own readahead and the kernel's clash - badly.
22 set it with blockdev to 8 (for example). Doesn't turn it off. Just makes
23 it none-obstrusive.
24
25 Turn off kernel's readahead for a visible performance boon.
26
27 use noop as io-scheduler.
28
29
30 > Has anyone tried hardened and ZFS together?
31
32 I did - I had some problems, but I'm not sure if they were caused by the
33 combination of ZFS and hardened. There were some issues updating kernel and
34 ZFS (most likely due to ZFS on root and me using ~arch hardened-sources and
35 the live ebuild for zfs). There are some hardened options that are known to
36 be not working (constify was one of them but that should be patched now). I
37 think another one was HIDESYM.
38
39 There is a (more or less regularly updated blogpost by prometheanfire
40 (installation guide zfs+hardened+luks [1]). So you could ask him or ryao (he
41 seems to support hardened+zfs at least to a certain degree).
42
43
44 Very interesting! What I want to experiment with is Pentoo on ZFS and then
45 downloading all the sources to create a secure gentoo installation
46 (hardened)_ by using Pentoo-amd64-2013.0_RC1.9.iso as the starting point.
47 Since the pentoo-installer script does not offer ZFS (yet), I thought I'd
48 just use SystemRescue (systemrescuecd-x86-3.8.1.iso) to set up ZFS? I do not
49 need luks, for this test system.
50
51
52 I have recently stopped using the option to
53 built ZFS into the kernel as I ran into problems with vdevs reported as
54 corrupt on the system I was trying this on. They weren't corrupt and
55 mounted fine in System Rescue Cd with modules, and the problem
56 disappeared when I switched to modules.
57
58
59 Plan carefully how you are going to create the vdev's before you add
60 them to a pool. Precisely my point, on a single 2T drive, or should
61 I add (required) a second 2T drive for this experiment. After I get
62 this to work, I have a 4 drive system to set up for testing......
63
64 http://wiki.illumos.org/display/illumos/ZFS+and+Advanced+Format+disks
65
66 Ok, so I have a single 2T seagate, or a pair of seagate 2T or 4 Green
67 2T WD drives to use for testing.
68
69 I just thoght a single drive rig would be fastest until I correct all
70 of the missteps (if it can go wrong in an install, I'll find it).
71
72 Just do ashift=12 and you're good to go.
73
74 So to recoup, my twist is to use the latest Pentoo install media,
75 becuase it is streamlined and yeilds a hardened system on top
76 of ZFS.
77
78 Anyone, care to splice in comments, suggestions or clarifications before
79 I invest some days in this venture?
80
81 curiously,
82 James

Replies

Subject Author
Re: [gentoo-user] ZFS formating Douglas J Hunley <doug.hunley@×××××.com>