X-Git-Url: https://git.proxmox.com/?p=pve-docs.git;a=blobdiff_plain;f=local-zfs.adoc;h=13f6050f6d8021dc2bc08d6a156c14c1ee69d6c6;hp=fab009336b9b1bfb9667564505b0c88e07288456;hb=a75eeddebed864bde81358463958ed1d166935e1;hpb=5eba07434fd010e7b96459da2a5bb676a62fe8b1 diff --git a/local-zfs.adoc b/local-zfs.adoc index fab0093..13f6050 100644 --- a/local-zfs.adoc +++ b/local-zfs.adoc @@ -1,6 +1,9 @@ +[[chapter_zfs]] ZFS on Linux ------------ -include::attributes.txt[] +ifdef::wiki[] +:pve-toplevel: +endif::wiki[] ZFS is a combined file system and logical volume manager designed by Sun Microsystems. Starting with {pve} 3.4, the native Linux @@ -57,7 +60,7 @@ ZFS depends heavily on memory, so you need at least 8GB to start. In practice, use as much you can get for your hardware/budget. To prevent data corruption, we recommend the use of high quality ECC RAM. -If you use a dedicated cache and/or log disk, you should use a +If you use a dedicated cache and/or log disk, you should use an enterprise class SSD (e.g. Intel SSD DC S3700 Series). This can increase the overall performance significantly. @@ -158,7 +161,7 @@ GRUB boot loader there. If you use a redundant RAID setup, it installs the boot loader on all disk required for booting. So you can boot even if some disks fail. -NOTE: It is not possible to use ZFS as root partition with UEFI +NOTE: It is not possible to use ZFS as root file system with UEFI boot. @@ -242,7 +245,7 @@ As `` it is possible to use more devices, like it's shown in If you have an pool without cache and log. First partition the SSD in 2 partition with `parted` or `gdisk` -IMPORTANT: Always use GPT partition tables (gdisk or parted). +IMPORTANT: Always use GPT partition tables. The maximum size of a log device should be about half the size of physical memory, so this is usually quite small. The rest of the SSD @@ -260,12 +263,19 @@ Activate E-Mail Notification ZFS comes with an event daemon, which monitors events generated by the ZFS kernel module. The daemon can also send emails on ZFS events like -pool errors. +pool errors. Newer ZFS packages ships the daemon in a separate package, +and you can install it using `apt-get`: + +---- +# apt-get install zfs-zed +---- To activate the daemon it is necessary to edit `/etc/zfs/zed.d/zed.rc` with your favourite editor, and uncomment the `ZED_EMAIL_ADDR` setting: +-------- ZED_EMAIL_ADDR="root" +-------- Please note {pve} forwards mails to `root` to the email address configured for the root user. @@ -297,14 +307,18 @@ time this value changes: ==== +[[zfs_swap]] .SWAP on ZFS -SWAP on ZFS on Linux may generate some troubles, like blocking the +Swap-space created on a zvol may generate some troubles, like blocking the server or generating a high IO load, often seen when starting a Backup to an external Storage. We strongly recommend to use enough memory, so that you normally do not -run into low memory situations. Additionally, you can lower the +run into low memory situations. Should you need or want to add swap, it is +preferred to create a partition on a physical disk and use it as swapdevice. +You can leave some space free for this purpose in the advanced options of the +installer. Additionally, you can lower the ``swappiness'' value. A good value for servers is 10: sysctl -w vm.swappiness=10 @@ -312,7 +326,9 @@ run into low memory situations. Additionally, you can lower the To make the swappiness persistent, open `/etc/sysctl.conf` with an editor of your choice and add the following line: - vm.swappiness = 10 +-------- +vm.swappiness = 10 +-------- .Linux kernel `swappiness` parameter values [width="100%",cols="