Comments on: HOWTO: Leopard Time Machine over iSCSI

By: Leho Kraav

Leho Kraav — Wed, 27 Jan 2010 21:50:50 +0000

@Anandha: afaik os x leopard boot disk doesnt know anything about iSCSI. dont have snow leopard, cant say anything about that. my strategy will be to restore with the help of another mac.

By: Leho Kraav

Leho Kraav — Thu, 07 Jan 2010 13:24:36 +0000

i can also report that initial impression of my setup of iscsi (gentoo + iscsitarget) based approach seems to be working pretty well. just don’t mount your time machine target simultaneously from two machines like i did at first (=instacorrupt journal and other fun) – forgot it wasn’t a network file system, although it sure feels like one

By: Anandha

Anandha — Wed, 25 Nov 2009 14:03:57 +0000

Can you restore over iSCI?

i.e. main hard disk dies, i boot off the snow leopard boot disk, and now can i restore the backup?

Thanks
Anandha

By: Caralluma

Caralluma — Mon, 07 Sep 2009 15:01:23 +0000

My mac freezes up everytime i start the back up. I’m still trying to figure out why. Thanks for the post anyway.

By: Aaron

Aaron — Thu, 21 May 2009 05:13:21 +0000

For what it is worth (almost 2 years from first post in this thread) I have this (Iscsi) working with FreeNas (0.7 amd64 now) with ZFS. Works a charm and getting up to 300-400Mbs over GigE from G5 iMac, Macbook Pro, Macbook and Mac Mini (Media Center). Local drives can not generate the output speeds that the server can take now. Total backups are about 4TB. No issues to date. My only concern is if I have to do a complete restore from scratch. Not sure how I am going to be able to mount the ISCSI backup drive

By: ChrisY

ChrisY — Thu, 23 Apr 2009 15:19:02 +0000

Havent played with iSCSI yet, but on my MBP with 4gb of ram I can backup just fine to an Openfiler 2.3 server SMB share. Wish it had AFP support, but I guess you cant have everything.

Chris

By: aliquis

aliquis — Mon, 05 Jan 2009 05:15:10 +0000

in what way wasn’t this reliable? So samba is prefered? Any router with samba share for a connected harddrive will work? I could have got an airport if they hade ONE with sound and disk support at onces, but it’s not like I will buy TWO

By: Steve Miller

Steve Miller — Mon, 22 Dec 2008 23:41:27 +0000

I was thinking of backing up my terabyte of data using Time Machine over iSCSI or another network protocol, but after reading these comments that doesn’t sound like a good idea. However, how Time Machine can back up to a Time Capsule over a wireless network connection without problems? What protocols are in use there? Can’t that be done over a wired connection, or using a different storage product?

By: Anonymous

Anonymous — Sat, 19 Apr 2008 17:25:17 +0000

Made it work like a champ… global iSCSI + Ubuntu 7.10 + iET + Linux RAID

I have 30 GB worth of time Machine backup running quite nicely…. Oh.. and since it’s LVM on linux it can snapshot the time machine. Without jumbo Frames I get 100Mb/sec transfer… one Intel Pro100MT NIC and the setup will be Jumbo Frames capable.
Copied several 6Gb DVD images… works great.

SMB w/ its locking & Disconnect semantics… SUX.

There is a REASON the variable is called “UnsupportedNetworkVolumes”…. because they don’t work.

By: DrFooMod2

DrFooMod2 — Wed, 27 Feb 2008 00:41:59 +0000

I wanted to report that I succeeded in using iSCSI (on an Openfiler server) with Time Machine via a gigabit link with jumbo packets enabled. The secret to my success? I used the iSCSI initiator from http://www.small-tree.com/. It appears as if the iSCSI initiator from globalSAN is just a plain broke down piece of shit. Well, you do get what you pay for. Oh well.

By: Pete McCollough

Pete McCollough — Mon, 24 Dec 2007 11:42:57 +0000

Ladies and Gentlemen,
I think the big piece of this discussion that is missing is the Jumbo Frame Capability of the switch and the tuning of the iSCSI server to meet the switch.

This is most likely the cause of the issues people are seeing.

Check this out:
http://www.byteandswitch.com/document.asp?doc_id=89589&page_number=2

By: Dick Davies

Dick Davies — Sun, 16 Dec 2007 22:57:04 +0000

What about the Nagle problem?

http://blogs.sun.com/constantin/entry/x4500_solaris_zfs_iscsi_perfect

By: Wouter

Wouter — Mon, 10 Dec 2007 13:21:44 +0000

Hi all,

I just want to report that I’m using iscsi/timemachine without any problem.

I’ve configured my Ubuntu Linux 7.10 Server with iscsi-enterprice-target. I installed Global San’s initiator on my G5. Over Gbit ethernet the transfer speed from server to server is about 20 – 30 mb/s.

I’m very happy with this setup because all the file management is native mac.

By: Jeff

Jeff — Mon, 12 Nov 2007 19:36:49 +0000

So much for it being the switch. I tried it with the Extreme Networks Summit 24 switch I have and it locked up solid almost instantly. Boy that’s annoying.

By: Jeff

Jeff — Sun, 11 Nov 2007 18:28:53 +0000

Brad,

I thought about the switch issues too. I almost bought an expensive gigabit switch the other day but couldn’t justify the cost. I have a Summit 24 10/100 switch that is more industrial strength that I’ve thought of testing with. The pity is it’s only 100 Megabit. I guess I’ll give it a go. I do like the fact that you can now use a network drive. Otherwise I guess I’ll put it on hold and wait for the native iSCSI support to appear in Disk Utility. It’s missing from the 10.5.0 release. (I’m totally bummed about that..)

Giacy, unfortunately that menu pick isn’t in my Disk Utility menu. Apparently it’s a feature that was removed prior to release. I’m wondering if it made it into Leopard Server. Any ideas?

By: Kirk

Kirk — Sun, 11 Nov 2007 18:13:22 +0000

Brad going with your new suggestion. Works like a charm. Thanks again. I will check your blog for more helpful advice on a regular basis.

By: giacy

giacy — Sat, 10 Nov 2007 22:32:03 +0000

Have you already tried to use the iscsi initiator function enbedded in disk utility for leopard?
http://www.thinksecret.com/archives/leopard9a377a/source/25.html

Ciao!!

By: brad

brad — Sat, 10 Nov 2007 02:03:19 +0000

Jeff / Kirk: I’ve begun running into the same issues as you both, and have discontinued using globalSAN for now.

I’ll be continuing to troubleshoot it though, as iSCSI support on the Mac is something I’m interested in from my days of working on storage projects with various employers.

Food for thought for you guys though, one thing I’m wondering about is the switches. While large file copies and older Macs may place less stress on a regular old network switch, faster Macs or aggressive activities like a Time Machine backup may make the Mac more dependent on SCSI control messaging. If the switch corrupts frames and resends have to take place, this might be exposing bugs in globalSAN.

I don’t know about you guys but the switches I’m using for my home LAN are pretty low-end. I’m going to try it with some higher end equipment as an experiment.

By: Jeff

Jeff — Sat, 10 Nov 2007 01:48:31 +0000

I just ran across your blog post while googling for Mac Pro lockups using GlobalSAN. I have openfiler 2.2 setup over a gigabit lan and my Mac Pro 3Ghz machine with 8 GB of RAM will lock up when transferring files to an iSCSI disk on the filer. However, my dual 2 Ghz G5 machine runs the globalSAN initiator connected to the same iSCSI share without issue. I’ve used Time Machine on the G5 and it backs up to the iSCSI disk flawlessly however it’s throughput is much slower than the Mac Pro. When it’s working, I’ve gotten between 35-60 MB/s on the Mac Pro whereas the Dual G5 averages around 10-20 MB/s. Anyone else have any comments? I’m looking for a way to make the Mac Pro reliable when connecting to the iSCSI disk. Maybe when Apple releases their built in iSCSI initiator in Leopard our problems will be gone. I hope so.

By: Kirk

Kirk — Thu, 08 Nov 2007 00:44:06 +0000

Same result. No problems with large file transfers at all. Time Machine still freezes the Mac it is running on. If you have any additional ideas regarding Time Machine let me know. Would love to get it working with iSCSI.