6.8 rollback or fix?

[pkcarlisle-dot-com]

Since 6.8 I have two highly unstable Linux boxes. USBs are not reliable, meaning a) that I have to go back to corded mice (no big deal) b) that USB wifi dongles do not stay online (and I even wrote a quickie script to ping one of several random DNS servers every few minutes to try to keep the wifi online, but no joy). Both boxes (one 32 bit and one 64 bit) have c) general freezing up requiring a couple of hard reboots per week (a very big deal since I advocated Linux to a user who now wants to know what garbage I installed and can I get rid of it (I installed 6.8 updates)) d) hard drive activity which remains constant for 30-40 minutes at a time, essentially locking down the system until a hard reboot. The kernel update a couple of days after the original 6.8 upgrade did not resolve all of this, although it did reduce the number of hard reboots required.

I have been researching already and have read that it's a major undertaking to roll back to a previous subversion, but this instability cannot continue. Since this is happening to two Linux boxes, I cannot be the only user with this problem. Is there a planned fix for the bugs in 6.8 or will a rollback option to 6.7 be made available or do I have to spend several weeks rolling it back piecemeal manually? BTW, 6.7 was fine. I only installed 6.8 because the system told me an update was available. I would happily continue with 6.7 if I could get back there.

(And before someone goes there, no, I did not make massive hardware changes to both Linux boxes coincidentally the same day that 6.8 came out...in fact I made no hardware changes to either of the Linux boxes except to remove the cordless mouse as above.)

[stevemowbray]

If there were major problems there would be a lot of reports here.
I have a couple of hundred boxes which have been upgraded to 6.8. I do not see any instability.

Perhaps you could post more details about your specific problems?

[forumitu]

Is there any third party add-on software on these servers? I am just wondering about the possibility of some software incompatibility.

[gulikoza]

You can try only reversing kernel to the latest from 6.7.

Usually kernel is not that tied to the other system software and most of the hw related problems are caused by kernel issues.
This is also the easiest option (as you can have multiple kernel versions installed and in case of even bigger problems, quickly switch back to 6.8 kernel).

[pkcarlisle-dot-com]

First, sorry for the delay in responding, but this CentOS box, post-updates to 6.8, now has all of the stability and functionality of Windows 98, and accessing forums, signing in and posting responses can take up to an hour if I'm lucky.

Things I see that are particularly worrisome with the new updates include the following:

My virtual machines in virtualbox no longer work. Virtualbox complains that it cannot update the kernel properly. (Kernel 2.6.32-642.1.1.el6.centos.plus.x86_64 by the way.)

USBs are not functioning properly. In addition to no reliable cordless mice, a wifi USB dongle cannot complete the installer script the way it has been doing successfully for the past year plus. Now I get multiple errors running the script including 'resource busy' In past, every time I had a kernel update, I would run a single long script which recompiled virtualbox kernel drivers, reinstalled the wifi dongle and reinserted xscreensaver into gnome as the default screen saver. With the new kernel, neither the wifi dongle nor virtualbox install.

The 64 bit box is very complex and has a lot of third party goodies and customizations (all of which were working fine until the 6.8 update). The 32 bit box is a purely low level end user machine and has virtually nothing fancy. It uses seamonkey (which is always closed out when done, chromium and vlc the same way) and that's about it. I set it up for some extreme end users who would not know how to corrupt a Linux box even if the wanted to, so it is very, very basic as far as installations.

Both the 64 and 32 bit boxes have the same USB wifi dongles (this is necessary...the only high speed ISP in the area provides a P.O.S. DSL modem which actively fights CAT5 (assuming that everyone uses wifi anyway)). The only way to give extreme end users anything like a reliable non-geekish experience is to connect to the Windstream modem/router through wifi. As with my 64 bit machine, the 32 bit has the same installer script to reinsert the wifi dongle driver which has to be run every time the kernel updates. As with the 64 bit machine, the reinstallation script of the dongle driver has run smoothly for the past year plus.

Some function is causing the hard drive to read or write excessively until the system locks up and needs to be manually rebooted on the 32 and 64 bit machines both. Disabling SELinux seems to reduce that a bit, but it still happens 2-3 times a week on both machines.

I really need to make a valiant attempt to drag the conversation back on topic here: I DO NOT care about the new sub-version. I do not need it. I prefer the previous subversion warts and all, with the attendant stability and functionality over the new and improved Windows 98-like experience. I also do not have multiple months to debug an operating systems upgrade. I'm not being facetious, I am just too busy to do this. So, please, back to topic: is there any way at all to roll back to the previous subversion on my 32 and 64 bit installations, and get functioning again?

There is a mention of the LAST 6.7 kernel...what is that number/version please? I did try using the last that was available in grub already, but no joy there.

[gerald_clark]

Do not use manufacturer supplied drivers.
GO to elrepo, read the FAQ and use their drivers.
They are the same drivers built in such a way that they do not need to be compiled after every kernel update.
You did not identify which wifi dongle you are using. Some are just junk and should not be used.

[pkcarlisle-dot-com]

Having a small period of free time in which to do so, I researched a downgrade from the minor subversion 6.8 to 6.7. Here is what I found and experienced...

It is (at least on paper) possible to downgrade from a minor subversion to another. Here is a link. The link says it, but Imma sayin' it, too: Use at your own risk!

https://access.redhat.com/solutions/186763

Now, here are some observations about the downgrade, or "downgrade", which is perhaps more accurate:

- Disable SELinux in grub for the kernel you will be using (to downgrade, my research from Red Hat's support docs suggested kernel 2.6.32-573.22.1.el6.centos.plus.x86_64). If you do NOT disable SELinux you may get the 'cannot load /dev/sda, bad magic number' sort of message which may induce heart attacks. Fiddling with grub and kernel strings is sooooo dangerous I don't even want to tell you how to do it here.

- I do not believe that the 'downgrade' was a complete and true downgrade. For instance, my box now boots in and reports a kernel 2.6.32-573.22.1.el6.centos.plus.x86_64 and version 6.5 BUT, the installer script I have run to insert virtualbox drivers and the wifi dongle is not usable any longer...vbox takes about five minutes now to grudgingly report (with warnings) a reinserted virtualbox driver (but my virtual machines do now load) and the wifi driver insertion portion now causes a kernel panic and crash. Therefore I do not believe that a downgrade was a true and complete downgrade. However, since the wifi dongle and virtualbox drivers WERE successfully inserted previously (when 2.6.32-573.22.1.el6.centos.plus.x86_64 was the current kernel) these drivers were already successfully installed at any rate.

- I note that wifi signal now reports as 100% again. When I was manually running a script to insert the wifi dongle driver, the result was always 100 signal strength (the router is 10 feet away as the crow flies so this was to be expected). After the upgrade to 6.8, signal dropped to 70% with a slower online response time as well. After the 'downgrade' signal is back to 100% (as one would expect at 10 feet). But again, this was *probably* because I had inserted the wifi driver in this kernel previously.

There was a question of the brand of wifi dongles. The brand is 'no-name-Chinese-prison-labor' brand. However, as with video cards, sound cards and the like, the *chipset* was known. It was a Realtek chipset and for the record, I did try native drivers first, over a year ago when I started using them, but could not get the dongles to come online. It does appear that they are natively supported in 6.8, but in a limited fashion, and with an unacceptable tradeoff.

I will be running this configuration for a week or so to see how stable it is (I cannot say if this resolves the crashing and freezing and excessive drive activity yet) before rolling this to the 32 bit box.

[TrevorH]

My virtual machines in virtualbox no longer work. Virtualbox complains that it cannot update the kernel properly. (Kernel 2.6.32-642.1.1.el6.centos.plus.x86_64 by the way.)

You need a patched version of VBox from Oracle to allow it to build under a 6.8 kernel. Look for 5.0.21 or higher.

[josageof]

When we are with 6.7 version, everything works fine. When upgraded to 6.8, much things was wrong.