Five Pounds of Flax

Every culture has a burrito.

Netgear WNR854T access point: comes with a bad power supply

Tuesday, December 30, 2008posted by Michael Rothwell @ 9:36 AM

If you intermittently lose your wireless connection, and you have a netgear rangemax access point, try swapping out the power supply. Apparently the one that comes with it is bad and causes the access point to reboot spontaneously. Since swapping power supplies, I've not had any problems with mine.


Time Machine, ZFS and iSCSI

Friday, December 05, 2008posted by Michael Rothwell @ 7:04 AM

I have an OpenSolaris file server at home.  I also have several Macs, which include Time Machine for backup services. I would like to have my household Macs back themselves up to the network server, but it's not easy to accomplish. Time Machine uses a goofy hard-link-farm method for making backups, and requires an HFS filesystem. It doesn't support network backup -- reliably. The SparseBundle format, which is used to create an HFS disk image on a remote file server, is prone to failure when the network disconnects, making future backups and restores fail until the sparsebundle is repaired (manually).

Apple is incorporating ZFS in to Snow Leopard, its next version of MacOSX. This would allow a tremendous improvement in backup service in OSX, because ZFS can make snapshots of filesystems and ship them over the network reliably. Simply having the mac make a snapshotof its local filesystem and send it to a zfs fileserver (running OpenSolaris, FreeBSD, OSX Server, Linux with fuse) would result in a reliable point-in-time backup.

Until we're all in ZFS nerdvana, I came up with another way to do backups to a network file server using Time Machine. Using Time Machine is convenient for users (my family in this case) because it has a nice, easy-to-use UI. One of ZFS' features on OpenSolaris is that it will export iSCSI targets. Using the free globalSAN iSCSI initiator for OSX, I mount an iSCSI volume from the fileserver and format it with HFS. Time Machine sees it as a regular local disk and makes backups to it as per normal. Time Machine works as expected. To prevent users (my family) from using the network backup volume as a regular disk, I hide it using SetFile:

$ SetFile -a V /Volumes/network-backup

Time Machine can still see it, but it's invisible in the Finder.

I wouldn't recommend this for computers connected via wifi, but it works very well for the iMac connected over ethernet.




sparsebundle won't mount, "resource temporarily unavailable"

Wednesday, November 19, 2008posted by Michael Rothwell @ 8:08 PM

If you're having trouble getting a sparsebundle disk image to cooperate with hdiutil, disk utility or just mounting via the finder, it's probably got an incomplete "band" due to a crash or inconvenient network disconnection (in the case of sparsebundles mounted from a network volume).

To fix it, delete (or more safely, move) the last "band" in the bundle (see thing.sparsebundle/bands). It should be the last one, sorted alphabetically by name, and probably the smallest.

I have a sparsebundle with World of Warcraft in it, stored on an Opensolaris (yay, zfs) machine and accessed via NFS. I took the laptop to work one day and forgot to unmount the sparsebundle. When I got back home, it wouldn't remount, saying "resource temporarily unavailable." Grr. Removing the last band fixed it.



Seasteading

Wednesday, April 16, 2008posted by Michael Rothwell @ 7:48 AM

The Seasteading Institute has opened its doors.
Mountain View, CA, April 15th, 2008. The Seasteading Institute today announced that it has been established in order to establish permanent, autonomous ocean communities to enable experimentation and innovation with diverse social, political, and legal systems. It will continue and expand on the work of Patri Friedman and Wayne Gramlich, authors of "Seasteading: A Practical Guide to Homesteading the High Seas".
Homesteading on the open ocean. Sounds exciting, but I would be afraid of storms and pirates.


Dr. Ron Paul doesn't accept evolution? Boo!

Saturday, December 29, 2007posted by Michael Rothwell @ 12:03 PM

Apparently Dr. Ron Paul doesn't accept the theory of evolution. Boo.
http://www.reason.tv/roughcut/show/215.html

This is not as bad as it would be for other candidates (Huckabee, for example), as Dr Paul is unlikely to establish any federal "faith-based" agencies, or dictate via the Department of Education how science should be taught in classrooms, etc. However, it's unfortunate that he turns out to be anti-intellectual regarding science.

It's true, as he says, that it's not the case that "anybody has absolute proof", however, science isn't based on absolute proof. That's a bad standard. Science is based on the best theory available at the time. An idea is considered "scientific" only if it is possible to disprove it. Science as a discipline seeks better and better explanations for physical phenomena over time, revising and discarding theories as necessary. A religion already has a set explanation of the universe and revises or discards facts to fit that explanation. Truly, if the universe is God's creation, then studying that creation scientifically is a way to better know "the mind of God" and poses no threat to religion. It may pose a threat to particular dogmas or political power structures, but not to religion itself.

It would have been nice for Dr. Paul to have given an explanation like the above, perhaps even mentioning that the Vatican recognizes evolution, rather than saying "I don't accept it" and giving a muddled endorsement of Creationism.


IMAP-IDLE version 1.07

Sunday, November 25, 2007posted by Michael Rothwell @ 10:40 AM

Version 1.07 of the IMAP-IDLE plugin for Tiger's Mail.app has been released.

This version asks Mail to fetch (not sync), due to user reports that sync caused excessive server load. I've received a request to optionally enable "sync", but have not (yet) implemented that feature. It also fixes a memory management issue that caused occasional crashes (unfortunately, not on my test machines -- but thanks for the crash reports!)


Windows mobile 5 "smartphone" is the worst phone software ever made

Friday, November 23, 2007posted by Michael Rothwell @ 9:25 PM

TSIA.

p.s. "Invalid Message Recipients".

POS.