storage - ZFS over iSCSI high-availability solution

I am considering a ZFS/iSCSI based architecture for a HA/scale-out/shared-nothing database platform running on wimpy nodes of plain PC hardware and running FreeBSD 9.

Will it work? What are possible drawbacks?

Architecture

Storage nodes have direct attached cheap SATA/SAS drives. Each disk is exported as a separate iSCSI LUN. Note that no RAID (neither HW nor SW), partitioning, volume management or anything like that is involved at this layer. Just 1 LUN per physical disk.

Database nodes run ZFS. A ZFS mirrored vdev is created from iSCSI LUNs from 3 different storage nodes. A ZFS pool is created on top of the vdev, and within that a filesystem which in turn backs a database.

When a disk or a storage node fails, the respective ZFS vdev will continue to operate in degraded mode (but still have 2 mirrored disks). A different (new) disk is assigned to the vdev to replace the failed disk or storage node. ZFS resilvering takes place. A failed storage node or disk is always completely recycled should it become available again.

When a database node fails, the LUNs previsouly used by that node are free. A new database node is booted, which recreates the ZFS vdev/pool from the LUNs the failed database node left over. There is no need for database level replication for high-availability reasons.

Possible Issues

How to detect the degradion of the vdev? Check every 5s? Any notification mechnism available with ZFS?

Is it even possible to recreate a new pool from existing LUNs making up a vdev? Any traps?

Comments

linux - Awstats - outputting stats for merged Access_logs only producing stats for one server's log

I've been attempting this for two weeks and I've accessed countless number of sites on this issue and it seems there is something I'm not getting here and I'm at a lost. I manged to figure out how to merge logs from two servers together. (Taking care to only merge the matching domains together) The logs from the first server span from 15 Dec 2012 to 8 April 2014 The logs from the second server span from 2 Mar 2014 to 9 April 2014 I was able to successfully merge them using the logresolvemerge.pl script simply enermerating each log and > out_putting_it_to_file Looking at the two logs from each server the format seems exactly the same. The problem I'm having is producing the stats page for the logs. The command I've boiled it down to is /usr/share/awstats/tools/awstats_buildstaticpages.pl -configdir=/home/User/Documents/conf/ -config=example.com awstatsprog=/usr/share/awstats/wwwroot/cgi-bin/awstats.pl dir=/home/User/Documents/parced -month=all -year=all...

iLO 3 Firmware Update (HP Proliant DL380 G7)

The iLO web interface allows me to upload a .bin file ( Obtain the firmware image (.bin) file from the Online ROM Flash Component for HP Integrated Lights-Out. ) The iLO web interface redirects me to a page in the HP support website ( http://www.hp.com/go/iLO ) where I am supposed to find this .bin firmware, but no luck for me. The support website is a mess and very slow, badly categorized and generally unusable. Where can I find this .bin file? The only related link I am able to find asks me about my server operating system (what does this have to do with the iLO?!) and lets me download an .iso with no .bin file And also a related question: what is the latest iLO 3 version? (for Proliant DL380 G7, not sure if the iLO is tied to the server model)

hp proliant - Smart Array P822 with HBA Mode?

We get an HP DL360 G8 with an Smart Array P822 controller. On that controller will come a HP StorageWorks D2700 . Does anybody know, that it is possible to run the Smart Array P822 in HBA mode? I found only information about the P410i, who can run HBA. If this is not supported, what you think about the LSI 9207-8e controller? Will this fit good in that setup? The Hardware we get is used but all original from HP. The StorageWorks has 25 x 900 GB SAS 10K disks. Because the disks are not new I would like to use only 22 for raid6, and the rest for spare (I need to see if the disk count is optimal or not for zfs). It would be nice if I'm not stick to SAS in future. As OS I would like to install debian stretch with zfs 0.71 as file system and software raid. I have see that hp has an page for debian to. I would like to use hba mode because it is recommend, that zfs know at most as possible about the disk, and I'm independent from the raid controller. For us zfs have many benefits, ...

Blog

Search This Blog