Linux isn’t perfect. I use it on a daily basis, and I know how great it can be, but it isn’t perfect. So what got my knickers in a twist today? Video drivers. Drivers of any kind can be a pain if the vendor doesn’t consider Linux worthy of support, but video drivers might be the most difficult since they can render a desktop fairly useless (get it? render! ha!)
In a lot of cases, the generic version of the driver is sufficient. There are some situations, though, where you need a real driver. In my department, we have a virtual map wall where the machines have two monitors each. In our forecasting lab, there are dual monitors (including two 42″ beauties!). The map wall machines have nVidia cards, and the forecasting lab machines have ATI. For installing the drivers, the strategies were different. The ATI machines have the drivers installed from a vendor-supplied installer. The nVidia machines used Dell’s Dynamic Kernel Module Support (DKMS) project.
With DKMS, you install the DKMS RPM, and then you can install whatever modules. Dell-nvidia for example. So when I did a kernel upgrade on RHEL4, it went like this:
up2date -u kernel kernel-devel ; reboot rpm -Uvh dell-nvidia-7664-3dkms.i386.rpm && gdm-restart
(or something like that at least). So silly me, I figured in RHEL5 it would work the same way, right? Ha! Maybe it is supposed to, but it sure didn’t. I spent hours this morning having a very heated, if one-sided argument with the combination of DKMS and Dell-nvidia. Un-installing, re-installing, re-configuring, swearing. Everything worked fine until I tried to enable the second monitor, and then things broke.
About lunch time, I decided to give up. I removed the DKMS RPM and found nVidia’s Linux installer. Ta-daa! I could use both monitors. Well that took far too long, but it finally worked. So now we’ll see what the procedure will be when the kernel gets upgraded. In the meantime, I hope I don’t have to think about drivers for a long, long time.
My desktop machine (which doesn’t have NEARLY as nice of monitors, but still has dual screens nonetheless) has a very interesting…quirk. When it boots, the NVidia kernel module is installed. At least, lsmod says it is. However it isn’t recognized at all until I rerun the NVidia setup program. I don’t know what it is that it does to make the module known, or maybe uninsert and reinsert it, but it works. I can kill the install midway through, I just have to start it to get the module recognized. Some day I’ll take the time to tear the installation script apart and figure it out.