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On Sun, Nov 27, 2011 at 01:22, Mick <michaelkintzios@×××××.com> wrote: |
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> On Friday 25 Nov 2011 20:08:01 Walter Dnes wrote: |
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>> On Fri, Nov 25, 2011 at 11:12:42PM +0700, Pandu Poluan wrote |
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>> |
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>> > Everytime I read some guide on LVM, my eyes becomes blurry, the room |
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>> > starts spinning, and I can hear wolves howling ... :D |
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>> > |
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>> > Seriously, LVM looks mighty nice, but it also looks (and is!) mighty |
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>> > complex. |
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>> > |
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>> > So, I want to start from something simple. |
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>> > |
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>> > Aaaanyways, after reviewing my production boxes, I decided to |
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>> > implement the following strategy: |
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>> > |
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>> > / == 800 MiB |
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>> > /boot == 20 MiB |
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>> > /usr == 1800 MiB |
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>> > /usr/portage == 2000 MiB |
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>> > /var == 4000 MiB |
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>> > /var/lib/postgresql == 1000 MiB |
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>> > |
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>> > Comments, suggestions, are welcome :) |
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>> |
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>> I have my own weird approach that's even weirder than my mdev setup<G>. |
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>> I start with... |
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>> * 250 megabytes for / as ext2fs (No that is not a typo) |
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>> * 4 gigs for swap |
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>> * the rest of the drive is /home as one huge reiserfs partition |
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>> |
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>> And I do *NOT* use LVM. "fdisk -l" shows... |
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>> |
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>> Device Boot Start End Blocks Id System |
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>> /dev/sda1 2048 976773167 488385560 5 Extended |
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>> /dev/sda5 4096 516095 256000 83 Linux |
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>> /dev/sda6 518144 8906751 4194304 83 Linux |
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>> /dev/sda7 8908800 976773167 483932184 83 Linux |
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>> |
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>> "df" shows |
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>> |
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>> Filesystem 1K-blocks Used Available Use% Mounted on |
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>> rootfs 247919 29315 205804 13% / |
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>> /dev/root 247919 29315 205804 13% / |
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>> devtmpfs 10240 0 10240 0% /dev |
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>> rc-svcdir 1024 44 980 5% /lib/rc/init.d |
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>> mdev 10240 0 10240 0% /dev |
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>> shm 1551308 0 1551308 0% /dev/shm |
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>> /dev/sda7 483917384 251951296 231966088 53% /home |
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>> |
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>> The secret is that I bindmount /opt, /var, /usr, and /tmp onto the |
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>> large reiserfs partition. |
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>> |
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> ########################################################################### |
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>> ### /dev/sda5 / ext2 noatime,nodiratime,async |
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>> 0 1 /dev/sda7 /home reiserfs |
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>> noatime,nodiratime,async,notail 0 1 /home/bindmounts/opt /opt auto |
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>> bind 0 0 /home/bindmounts/var /var |
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>> auto bind 0 0 /home/bindmounts/usr /usr |
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>> auto bind 0 0 /home/bindmounts/tmp |
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>> /tmp auto bind 0 0 /dev/sda6 |
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>> none swap sw 0 0 /dev/cdrom |
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>> /mnt/cdrom iso9660 noauto,users,ro 0 0 /dev/cdrom1 |
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>> /mnt/cdrom1 auto noauto,user,ro 0 0 /dev/sdb1 |
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>> /mnt/extb auto noauto,user,noatime,async 0 0 /dev/sdc1 |
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>> /mnt/extc auto noauto,user,noatime,async 0 0 |
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>> |
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>> # glibc 2.2 and above expects tmpfs to be mounted at /dev/shm for |
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>> # POSIX shared memory (shm_open, shm_unlink). |
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>> # (tmpfs is a dynamically expandable/shrinkable ramdisk, and will |
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>> # use almost no memory if not populated with files) |
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>> shm /dev/shm tmpfs nodev,nosuid,noexec 0 0 |
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>> |
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> ########################################################################### |
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>> ### |
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> |
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> I recall your interesting mounting approach, but never really understood the |
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> benefit of it. Would you please explain why you use bindmount? |
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> |
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|
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Not really explaining waltdnes' interesting layout, but using |
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bindmount (instead of symlinks) ensures that when a program tries to |
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find a relative directory from a path, it will not attempt to do so |
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from the symlink's target. |
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E.g.: |
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Say I have /lib/gzampl/, which is actually a symlink/bindmount to |
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/mnt/gzampl/. Then theres another directory /lib/morethings. With a |
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symlink, if a program wants to do "../morethings" from within |
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/lib/gzampl/, it might end up in /mnt/morethings if the program tries |
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to resolve the symlink first. With a bindmount, doing "../morethings" |
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from /lib/gzampl/ will always end up in /lib/morethings. |
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(CMIIW) |
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|
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That said... mentioning bindmount made me rethink things... |
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What if I have: |
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/mnt/.temporaries ==> ext4, 4GiB |
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/mnt/.persistents ==> reiserfs, 2GiB |
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then I make some directories and bindmounts: |
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/mnt/.temporaries/tmp --bm--> /tmp |
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/mnt/.temporaries/vartmp --bm--> /var/tmp |
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/mnt/.temporaries/run --bm--> /run |
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/run --bm--> /var/run |
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/run/lock --bm--> /var/lock |
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/mnt/.persistents/postgresql --bm--> /var/lib/postgresql |
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/mnt/.persistents/vardb --bm--> /var/db |
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/mnt/.persistents/varlog --bm--> /var/log |
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/mnt/.persistents/varspool --bm--> /var/spool |
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Ta da! The ephemeral directories can now just fight among themselves, |
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and the important directories can be backed up in one fell swoop (via |
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/mnt/.persistents)? |
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Thoughts are welcome, of course :) |
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Rgds, |
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-- |
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FdS Pandu E Poluan |
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~ IT Optimizer ~ |
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|
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• LOPSA Member #15248 |
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• Blog : http://pepoluan.tumblr.com |
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• Linked-In : http://id.linkedin.com/in/pepoluan |
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