Gentoo Archives: gentoo-user

From: meino.cramer@×××.de
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] backup hardware setup
Date: Tue, 24 Jun 2014 18:35:19
Message-Id: 20140624183423.GB3869@solfire
In Reply to: Re: [gentoo-user] backup hardware setup by Alan McKinnon
1 Alan McKinnon <alan.mckinnon@×××××.com> [14-06-24 20:00]:
2 > On 24/06/2014 19:32, meino.cramer@×××.de wrote:
3 > > Alan McKinnon <alan.mckinnon@×××××.com> [14-06-24 19:12]:
4 > >> On 24/06/2014 16:43, meino.cramer@×××.de wrote:
5 > >>> Hi,
6 > >>>
7 > >>> I bought two identical external harddrives, USB 3.0, with 1 TByte each
8 > >>> (no SSD - the good ole mechanical ones...;).
9 > >>>
10 > >>> The intended use is for backup of longer files. The drives will
11 > >>> contain the same contents.
12 > >>>
13 > >>> Currently there are still "clean metal" (no partitioning, no fs).
14 > >>>
15 > >>> Data integrity and recoverability (Uhhh...that words looks wrong...) in
16 > >>> case of an desaster is more important than speed.
17 > >>>
18 > >>> What is the recommended way of partitioning ?
19 > >>> What filesystem to choose?
20 > >>>
21 > >>>
22 > >>> Thank you very much in advance for any help!
23 > >>> Best regards,
24 > >>> mcc
25 > >>>
26 > >>>
27 > >>> PS: Running vanilla kernel 3.15.1....
28 > >>
29 > >> You haven't given much in the way of detail, so I assume you have
30 > >> regular needs, nothing fancy, and it's all a bunch of files right?
31 > >>
32 > >> In that case, partitioning and filesystem type are largely irrelevant as
33 > >> long as you don't have corruption. With one caveat:
34 > >>
35 > >> You must always make sure the source drive is intact and ok. If not, and
36 > >> you back it up anyway, then you are already toast (you will overwrite
37 > >> your last backup with new faulty data).
38 > >>
39 > >> There's several approaches to how to do the transfer:
40 > >>
41 > >> If you have say a general fileserver with lots of files that don't
42 > >> change much or often, just rsync everything in one go. There is no
43 > >> optimization you can do that will perform much faster than rsync.
44 > >>
45 > >> If you have a big busy filesystem that changes often and lots, then use
46 > >> lvm (or anything that can make snapshots) and rsync that.
47 > >>
48 > >> If you have a huge database where everything is changing all the time,
49 > >> don't do filesystem copies, use the tools provided by the db vendor. I
50 > >> doubt this is your need as you would have said so, but it's worth
51 > >> mentioning.
52 > >>
53 > >>
54 > >> --
55 > >> Alan McKinnon
56 > >> alan.mckinnon@×××××.com
57 > >>
58 > >>
59 > >
60 > > Hi Alan,
61 > >
62 > > thanks for your reply! :)
63 > >
64 > > Yes...your are right. I have a lot static (=not changing) data on my
65 > > harddisk...mostly things like video tutorials (blender), videos of
66 > > birds I filmed, dokuments and such...
67 > >
68 > > They are eating up the space on my systems harddisk.
69 > >
70 > > Do I decided to put them on a extern hd and an identical copy on
71 > > another identical external harddisk.
72 > >
73 > > Its mainly a task of updateing the data on the external drives with
74 > > that what is new (and static and big and falls under what I described
75 > > above) on my systems harddisk.
76 > >
77 > > I will check rsync for that!
78 >
79 >
80 > That changes things just a little bit - I thought your two drives were
81 > going to be one for live and one for backup. Do you intend to move these
82 > files off your main drive onto the identical externals, or just copy the
83 > files?
84 >
85 > I would have those two external drives using different filesystems, just
86 > in case as they are your only copy and external drives are fragile in
87 > use and in storage. Exact fs type doesn't really matter - ext4 and xfs,
88 > or ext* and btrfs, it's all good.
89 >
90 > Just do make sure you don't use rsync with --delete for this :-)
91 >
92 >
93 >
94 > --
95 > Alan McKinnon
96 > alan.mckinnon@×××××.com
97 >
98 >
99
100 Yes, I will delete the data from my systems drive...
101
102 You wrote:
103 "I would have those two external drives using different filesystems"
104
105 Different to what? Different to the fs on the system drive? Both
106 external drives use different filesystems? All three use different
107 filesystems?
108
109 And how can this help, if the drives are fragile? (I understand
110 "fragile" as "mechanical not robust" (sorry I am no native english
111 speaker))
112
113 I will use this "mobile disks" not really as the word "mobile" implies. They
114 will only "travel" manually between a secure place and my PC.
115 When in use, they will rest on the floor of the room (so they can not
116 be dropped) and _under_ the case of my PC (ole school big tower metal
117 case with a gap between the bottom of the case and the floor of the
118 room.)

Replies

Subject Author
Re: [gentoo-user] backup hardware setup Alan McKinnon <alan.mckinnon@×××××.com>