Thursday, December 27, 2007

Re: MacBooks and Wireless problem

Glen,

On Dec 26, 2007, at 12:38 PM, Glen Worthing wrote:

> Hi,
>
> We have been having the same problem at our school but it's not
> only with
> wireless, wired units are doing it as well. We were using Apple
> Airport
> Base Stations and now we have an Xirrus A/B/G wireless network
> running. The
> units (25) in the lab that are wired are connected through Netgear
> 10/100
> switches. We are using Workgroup Manager as well in an OS 10.4
> (server &
> client) environment running eMac's, iMac's and MacBooks.
>
> Same type of setup I would assume. We do have the home directories
> automount.

There are two separate issues at play here.

1. Apple recommends a minimum client computer connection speed of
100MB in order to successfully automount users' home directories;
under current wireless protocols it is not possible to meet this
baseline and as such Apple does not recommend automounting users'
home directories via a wireless connection. It is possible to
automount via wireless, however performance will be quite slow and
progressively become slower and more problematic as more laptops
attempt to automount via a single wireless access point.

For the past several years we have had our student laptops configured
for auotmounting users' home directories for those instances when
users wished to connect a laptop to the network via a wired port,
with the recommendation that when using the laptop in a wireless mode
they should login via a generic local account and then use the
Connect to Server.. item in Finder to access documents in their home
directories. Unfortunately several of our user groups have not
followed this recommendation and have complained about unacceptable
performance via wireless home directory logins. We found that none
of these laptops were being connected via wired connections and as a
result during this Winter Recess break we have reconfigured our
laptops so as to not use automounted home directories logins, all use
will now be via generic local logins on each laptop.

2. We too have been battling what I term the 'stuck connection'
issue reported by Spook; user logs out but still shows as an active
disabled/asleep AFP connection in the Server Admin pane with the user
not being allowed to login from another computer due to already being
logged in from another computer. Sometimes a restart of the client
computer will resolve the issues, sometimes not - requiring a manual
disconnect in the Server Admin pane. We have also observed the
problem to be more prevalent on Intel vs. PPC Macs.

We have been able to reduce (but not eliminate) the 'stuck
connection' issue by implementing several AFP tuning techniques, the
best source of information for these tuning techniques can be found
at http://www.afp548.com/

The value we adjusted at the cli level
that seems to have had the most impact was afp:reconnectTTLInMin =
1440 (the default setting) down to afp:reconnectTTLInMin = 10. We
will be readjusting this down to 5 minutes during the Winter Recess
break.

Hope This Helps,

Mark

Mark Nelson
Director of Information Technology
Thayer Academy
745 Washington Street
Braintree, MA. 02184

voice: 781-664-2264
fax: 781-380-0515
email: mnelson@thayer.org

http://www.thayer.org

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