The Brother MFC7820N is quite an old all-in-one mono laser printer, colour scanner and fax machine. The one I have is about 15 years old now, but still works fine. You can still get toner, drums and other spares for it.
I have used the network scanning functionality with Linux previously, but a long time ago now, on one of my previous laptops. I needed to get it working on my current laptop, which is running Ubuntu 22.04 LTS.
More problems with Ubuntu 10.04 on Samsung N510
My main laptop’s hard disk died at the weekend, so I started migrating all my data to my Samsung N510 netbook (thank goodness for backups). Unfortunately, I hit this Ubuntu 10.04 bug, which meant my netbook was crashing sporadically when I ran lots of programs – firefox and thunderbird simultaneously:
Bug #539482: Page allocation failures on Dell E5500
I tried installing mainline 2.6.34 kernel builds, as described by the Ubuntu Wiki Kernel/MainlineBuilds page. The 2.6.34 kernel seemed to hang the netbook hard.
Upgrading to Ubuntu Netbook Remix 10.04 - no title bar or window decorations
I upgraded from UNR 9.04 to 10.04 the other day, and found that the window decorations such as the title bar and close/maximize/minimize had disappeared from all windows (even in “GNOME” log-in sessions).
My particular problem seemed to be caused by saved GNOME session state. I’ve attached a suggested resolution to Launchpad bug #576696.
After upgrading to Fedora 12, I found that scrolling in Firefox was painfully slow. I’m using the Nouveau driver with a Geforce Go 5700 chip in my old 3.2 GHz Athlon64 laptop. Scrolling seemed to peg the CPU usage at 100% and render the computer unusable for the duration of the (very slow) scrolling.
Disabling “smooth scrolling” in the general section of the preferences seems to have fixed this.
Fedora 9 vs. VMware-server 1.0.8
VMware-server 1.0.8 seems to barf on the GTK+ theme files shipped with Fedora 9. I’m using Clearlooks. You can force VMware-server to use the system GTK+ libraries:
export VMWARE_USE_SHIPPED_GTK=no
vmware &
On my F9 x86_64 install, I needed to install a few i386 packages first, before VMware start. VMware-server is an i386 program, so you need these i386 packages to be installed for it to be able to use the system GTK+ libraries:
Thanks to Linux desktop developers
I’ve just caught up with 2 years’ worth of Linux desktop developments (NetworkManager works, user switching, built-in volume controls working on my laptop). I like. Thanks for all the hard work, Linux desktop developers!
PS: Turning on "subpixel aliasing" has made text much more readable.
Knowing what rpms you’ve just built
One idiom I’ve found myself repeating in various projects is a build-all script that builds multiple rpm packages in a certain order. This isn’t very sophisticated – each time I’ve ordered the packages being built manually.
But how do you know what rpms you will get, when you run rpmbuild? You need to know this, so you can install the rpms. Here is a solution:
rpm: Filtering dependencies differently for different subpackages
Recently I was trying to work out how to filter rpm Requires/Provides dependencies differently for different subpackages. I was trying to produce a subpackage that was the same as another subpackage, but stripping out some library dependencies. Call the one subpackage foo
and the other foo-nodeps
. (Don’t ask why I was trying to do this.)
rpm has a way of hooking the dependency generation, as described in FilteringAutomaticDependencies at the Fedora wiki. This is pretty magical. You disable rpm’s internal dependency generation. You can then override the default external dependency generation scripts (if you want). Normally rpm uses find-requires
and find-provides
in /usr/lib/rpm
, or /usr/lib/rpm/redhat
on some Red Hat or Red Hat-derived systems. If you do override the scripts, it’s likely you’ll want to call them and filter their output.
postfix config-o-rama
I spent a lot of today finally setting up e-mail for my domain, phekda.org. My goals were:
- Set up an SMTP SUBMIT server (running on port 587), so that I can send mail from
@phekda.org
addresses from anywhere.
- Require mail to be submitted over TLS.
- Authenticate the client by requiring that the client presents a certificate issued by my private certificate authority (CA). Since I’m only going to issue certificates to people/machines I trust, possession of a certificate is implicit authentication.
TinyCA
I used TinyCA2 to set up my own personal CA. It’s really easy to use. I created a CA for phekda.org. I also created a “bad” CA for testing that my postfix box would only accept certificates issued for phekda.org.