Currently Being ModeratedAug 14, 2012 12:42 PM (in response to RichardFromRouyn-Noranda)
I have this problem too! 80 Gb to backup through network to my Mountain Lion server with attached external drive....6 DAYS!?!
Currently Being ModeratedAug 21, 2012 6:30 AM (in response to RichardFromRouyn-Noranda)
Another Mac user reported the same experience and the same problem (http://iansutherland.ca/2012/08/15/slow-time-machine-network-backups-in-mountain -lion/). From his experience, he pretends that Apple intentionaly slowed downTime Machine backup on remote host in Mountain Lion to promote use of OS X Server.
Currently Being ModeratedAug 24, 2012 9:46 PM (in response to RichardFromRouyn-Noranda)
This matches my experience exactly. I can also confirm that buying and installing Server does cause the backup speed to return to normal, but I don't think this (the slowness) is intentional on Apple's part, I expect a 10.8.x patch will address whatever is causing the problem.
Currently Being ModeratedAug 28, 2012 12:31 PM (in response to RichardFromRouyn-Noranda)
I was suspicious that installing Server would fix this, but after the 10.8.1 update didn't change anything I decided to try.
Before installing Server, Time Machine was estimating it would take weeks to backup my 10.8.1 system to another 10.8.1 system over gigabit ethernet (though regular file transfers were fast as expected). After installing Server and enabling Time Machine in the Server app, my Time Machine backups over the network are now back up to the same speed they were under 10.7.
Currently Being ModeratedAug 30, 2012 7:15 PM (in response to Brandt Kurowski)
Same problem also, backing up to a SynologyNAS 212+, normal file transfers are blazing fast. Created a new backup after reformated HD, currently backing up 241 GB and saying 2 days! It seems to be an issue with Mountain Lion as my old backup from Lion was running fine on the same SynologyNAS since March 2012. Currently running OS X 10.8.1 on an iMac 27" i7 16 GB Memory. The only change is partitioned 250 GB for Bootcamp and WIN 7 ( don't say it I know! ) Hope Apple is listening??iMac (27-inch Mid 2010), Mac OS X (10.7.3), 2.93 GHz Intel Core i7 16 GB
Currently Being ModeratedAug 31, 2012 1:14 AM (in response to RichardFromRouyn-Noranda)
Problem solved! Installed OS X Server from App Store!
Currently Being ModeratedAug 31, 2012 11:18 PM (in response to Stewart Carlsson)
My issues is also resolved, deleted the timemachine prefs created a new backup, completed 288 gb in just under 3hrs!
(Synology DS212+). Works great again as before.
Currently Being ModeratedSep 1, 2012 7:03 AM (in response to Akitaguy)
But you don't had the exact same problem that I originally wrote about and that others experienced too. You had a problem backing up to a NAS from Mountain Lion. We have a problem backing up to a host running Mountain Lion (but no problem from Mountain Lion to a Lion host).
Currently Being ModeratedOct 5, 2012 4:33 PM (in response to RichardFromRouyn-Noranda)
Experiencing the same thing here with OSX 10.8.2: Timemachine is extremely slow on my Mac Pro when using a drive on my Macbook Pro on the same network.
I am using a programm called iStat Menus to track some of my machine's activities, so I decided to track the network activitiy as well during a Timemachine back-up session.
My machines are connected to the network at 1000baseT speeds. However, when Timemachine starts on the Mac Pro the speeds are only around 80KB/s. While the back-up is still in progress, I switched to the WiFi network. All of a sudden the speed jumps to 5MB/s! When going back to the wired network connection, it even jumps to 30MB/s and the back-up finishes very quickly (like it always did before upgrading to Mountain Lion).
However, when Timemachine starts its next session after an hour, it goes back to the very low 80KB/s speeds.
It must be just a very simple setting in Timemachine that needs changing. Apparently this was done in the update for OSX 10.7.5, which also had Timemachine speed problems.
Currently Being ModeratedOct 9, 2012 1:56 PM (in response to RichardFromRouyn-Noranda)
I have the same problem after upgrading my machines from 10.7.5 to 10.8.2. One iMac has an external HD that serves as backup destination for all computers. It is shared by the hosting iMac. Local TM backups are as fast as ever, but TM backups from other machines to this remote disk are very slow now.
Yesterday I managed to get a fast backup on a macBook by following the instructions mentioned here:
However, this is not what I want. I have to mount the external disk manually before running TM. Before TM mounted the disk itself.
Something went wrong in Mountain Lion with Time Machine, for that I am sure. I really hope Apple did not do this on purpose. If so, I would be very disappointed.
Currently Being ModeratedOct 25, 2012 7:00 AM (in response to Jan Mostert)
I am in the same boat. I am thinking of installing server app. Is that best the solution?
Currently Being ModeratedOct 25, 2012 1:00 PM (in response to Dimme)
Based on the experience of Brandt Kurowski and Stewart Carlsson reported above, I would say yes if the Mac is used only as a server or if it's not a problem for you working on a machine with server OS.
On my side, I didn't have solved the problem yet. And I'm surprised that this have not been addressed by Apple yet.
I don't want to use OS X Server on my machines wich are of day to day use. But I'm near of a solution: someone offered me a used Mac Mini; I will run this one as a server with Lion and I will plug the external drives on it. As a side benefit, I will have a server permanently available.
Currently Being ModeratedOct 25, 2012 2:47 PM (in response to Dimme)
Installing Server seemed to fix the problem for me at first (before I installed Server, Time Machine was slow, after I installed it, speeds were reasonable), but sometime in the last few weeks things got slow again (without me having changed anything on the server). YMMV, but it no longer appears to be a silver bullet.
Currently the only way I get decent throughput with Time Machine is to unplug my Ethernet and just use WiFi instead.
Currently Being ModeratedOct 25, 2012 7:19 PM (in response to RichardFromRouyn-Noranda)
I just installed server and started a fresh time machine backup. Looks like it going pretty fast. Sayes it will be done in 2 hours, not 6 days like before. Before server it would take 20 minuntes before it would even start to copy(said prepairing) now it started right away.