[mario_capo]

So, I am not the most computer literate, and I think this was answered on here already. Can I attach another external Hard Drive to a Time Capsule through the USB and back up info on it wirelessly just like the Time Capsule's hard drive??

[Jason Snell]

Glenn_Fleishman said:

>As I look at Time Capsule, I'm struck by how seemingly limited it is compared to an external drive attached to one of your Macs on a network.

As I see it, the appeal of Time Capsule is that it's for people who don't leave a Mac on 24/7 for backup purposes. (I have such a Mac, so it's not as big a deal for me.)

[folklore]

Jason Snell said:

As I see it, the appeal of Time Capsule is that it's for people who don't leave a Mac on 24/7 for backup purposes. (I have such a Mac, so it's not as big a deal for me.)

It would also be nice for people that just have laptops. Having to tether yourself to a desk sorta defeats the purpose of being all mobile-like. :)

[awinkler]

It is also good for people who want fewer boxes and cables in their living or work spaces. :-)

[wassimj]

[quote name='folklore']
>

Jason Snell said:

>
> As I see it, the appeal of Time Capsule is that it's for people who don't leave a Mac on 24/7 for backup purposes. (I have such a Mac, so it's not as big a deal for me.)

It would also be nice for people that just have laptops. Having to tether yourself to a desk sorta defeats the purpose of being all mobile-like. :)

Absolutely. I have a MacBook and used to work at my desk in the basement and connect to a TimeMachine LaCie disk via USB and backup regularly. Then we had to renovate/paint and I started working away from the desk and the disk. So, naturally I fell off the backup wagon. TimeCapsule is a great solution for those with roaming portables (and those who prefer simpler and neater setups).

[DavidCar]

Will using "sudo sysctl -w net.inet.tcp.delayed_ack=0" make the transmission process less reliable, particularly in a noisy environment?

[alinnova]

In home use, for the past several years on occasion, I have backed up the User data on our main desktop Mac to a second internal hard drive, to CD-ROMs, and to a laptop via Target Disk Mode. We will soon be running two iMacs, a MacBook, and an iBook G4, all with Leopard 10.5.2.
Better backup alternatives now include external FireWire hard drives with Carbon Copy Cloner or SuperDuper, Time Machine with FW or USB external drives, and Time Capsule.
After reading through this thread, I understand that we cannot partition the drive in Time Capsule. Therefore, Time Machine would manage all back ups from four Macs seamlessly on one Time Capsule volume. True?
Also, we cannot boot or start up any of these Macs from Time Capsule. True?
I hope Glenn Fleishman's full review makes these points clear.
Thanks,
Al

[Glenn_Fleishman]

dduff617 said:

i already have both an airport extreme-n and an always-on osx server running. i'd like to be able to use one or both as backup servers with (very) large disks attached. here are some questions i would like to see answered:

what protocol does time machine (TM) use to talk to time capsule (TC)? i.e., is it afp, smb, some special variant of them, or something else?

AFP.

Quote

is there some particular set of afp or smb functions (open, close, read, write, seek, delete, etc.) that TM uses to an unusually large degree? does it always just open one big image file on the remote disk, as reports seem to indicate?

It uses sparse images (this is well documented), which is a specific kind of disk image that can grow over time. It mounts the sparse image as a local volume to which it writes files.

Quote

is there something about the filesharing implementation on a TC which somehow enhances the reliability of TM? i.e., there has been talk of that possibly writes don't return until data has been written out to disk (vs. just to cache, for example). this might also explain why performance is slow relative to a normal file server.

Not as far as I can tell, but I'm not doing protocol-level examinations.

Quote

if TM performance is enhanced in some way (i.e., better reliability) by a special implementation/configuration of filesharing in TC (such as write-through caching or something), is this enhancement something that can be achieved on a regular osx fileserver? is it a property of AppleFileServer (or smbd or whatever) or is it a property of how the drive is mounted on the server? or both?

No.

Quote

does an afp server have to be configured on the server side to support TM when the share is set up? (probably) ...or is there some kind of AFP request that can be used to enable it? (seems unlikely)

Yes, just like the AirPort Extreme.
does achieving TC-like functionality depend on the drive hardware being used (e.g., "server-grade" hard drives, etc.) as was hinted in the pre-release product description? seems unlikely, but if so, how?

No, there's a default you can change (see far earlier in these comments) that enables the use of any AFP volume for Time Machine, thus it's hard to believe that "server grade" matters, which refers to speed and reliability, nothing else.

[Glenn_Fleishman]

DavidCar said:

Will using "sudo sysctl -w net.inet.tcp.delayed_ack=0" make the transmission process less reliable, particularly in a noisy environment?

No. It simply changes how the TCP stack waits for acknowledgements from a remote server. This means that in cases in which the remote server doesn't send such acknowledgements, with this value set to 0, data continues to be sent. TCP is a "reliable" protocol, which means that if packets fail, they are retransmitted. Likely in a noisy environment, this setting would reduce throughput.

[Glenn_Fleishman]

Quote

Better backup alternatives now include external FireWire hard drives with Carbon Copy Cloner or SuperDuper, Time Machine with FW or USB external drives, and Time Capsule.

After reading through this thread, I understand that we cannot partition the drive in Time Capsule. Therefore, Time Machine would manage all back ups from four Macs seamlessly on one Time Capsule volume. True?

Right. It creates sparse images, one for each machine, which is an expandable disk image format. It can be mounted, and that's in fact how Time Machine handles writing the backups.

Quote

Also, we cannot boot or start up any of these Macs from Time Capsule. True?

You can use the Leopard boot DVD to restore a disk from any Time Capsule backup. You can also use Time Capsule with Migration Assistant. But you can't boot from it. I haven't thought about whether you could use some clever method of mounting the sparse image and then booting from that; that could be possible.
[quote]
I hope Glenn Fleishman's full review makes these points clear.

[charliego7]

Would it be possible to use the drive in time capsule as a Time Machine drive for a mac wirelessly networked, while using another usb drive plugged into the TC USB port as a Time Machine drive for a different mac that was hard-wired into the same network?
Thanks

[People_Eater]

FTA:
"a small envelope with an installation disk"
What??? Apple's gone back to 3.5" floppy disks? Now that would really be news. I think you mean a "disc" or more specifically, a CD or DVD.

[People_Eater]

gpasq said:

If you want to spend $500 to do a 15 hour restore and be down the entire time, go ahead. Seems silly to me. I feel it's better to spend a couple hundred for a USB attached drive and be back up and running in under an hour. But hey, that's just me.

That doesn't make any sense. Gigabit ethernet (which the Time Capsule has) is FASTER than USB 2.

The difference in speeds is likely due to the way that Time Machine works, not the USB connection versus ethernet or wireless, or whatever. The problem with your comparison is that you were using a different backup method. If you were using Time Machine instead of (insert other backup software here), then you would probably find that the backup/restore to your directly-attached USB drive is likely to be just as slow. Or, if you used your backup software with the Time Capsule hardware, it would be just as fast (or faster) if connected via gigabit ethernet.

Which brings me to the question - if you want fast backups/restores, why did you choose a USB drive, instead of Firewire?

[Glenn_Fleishman]

People_Eater said:

FTA:

"a small envelope with an installation disk"

What??? Apple's gone back to 3.5" floppy disks? Now that would really be news. I think you mean a "disc" or more specifically, a CD or DVD.

What's the famous quote? "Picky! Picky! Picky!"