Linux Kernel 5.4 and VirtualBox Puzzle

I've been puzzling over WHY my VirtualBox doesn't work under Linux kernel 5.4 ever since 5.4-RC1 came out.  Last week, Slackware -current made 5.4 the default kernel so I hoped all was well - NOPE!  So I compiled it myself adding in the modules that have always allowed everything to work up until 5.3.x.  That didn't work either.  Bummer.

So I did a bit of research (5 seconds of googling) and it seems there was a lot going on with VirtualBox and Linux kernel 5.4.  First there was this:

Linux 5.4 kernel will no longer make interfaces available so that arbitrary kernel modules may modify page attributes to turn the executable bit on/off. Virtualbox currently is one of such kernel modules doing that.

 Then, it seems, in 5.4-RC7 they added a special "shared folder" area for Virtualbox which was later removed. 

So, at this time, it seems VirtualBox and Linux kernel 5.4 are not going to play well together until a special new VirtualBox 6.1 candidate is released (designed specifically to work with VirtualBox).  So far, I cannot find this release candidate (5 seconds of googling).

That's ok, I have my box set to always my special vanilla 5.3.x (5.3.15 at the time of this writing).  I just hope this continues to get updates so I don't have to drop back to the 4.19.x LTS kernel.

If you see a release candidate for VirtualBox 6.1 post a response.  I'll do the same (so we're racing).

Slackware and LXC

I have a fresh Slackware 14.2 I've been enjoying since it came out this month.  I needed a hyper-visor and was getting ready to add Xen (the hyper-visor of choice on Slackware).  I like Xen, but I knew the compile times for the Slackbuilds and it's dependencies would probably take more time than I had at the moment.  Then I remembered LXC.  It comes with.

I didn't know much about LXC so did some quick reading.  They say "it's similar to Docker but easier" - I like the sound of that.  So I check it out.  It's EXACTLY like Solaris containers!  Which I've been using for over 10 years - but, again, easier!  It's pretty slick!  And it installs by default on Slackware 14.2 but there's a few things you need to change.

ON THE HOST

Edit the /etc/rc.d/rc.inet1.conf

Slackware does not have a bridged network device by default BUT it does have it defined and commented out.  I found this works nicely except I was expecting my host interface to use eth0 and lxc guest to use br0.  It was not what I expected but it works fine!

# Example of how to configure a bridge:
# Note the added "BRNICS" variable which contains a space-separated list
# of the physical network interfaces you want to add to the bridge.
IFNAME[0]="eth0"
BRNICS[0]="br0"
#IPADDR[0]=""
#NETMASK[0]=""
USE_DHCP[0]="yes"
#DHCP_HOSTNAME[0]=""

Routing = Yes

You will, of course, need your host to route packets so

# chmod 755 /etc/rc.d/rc.ip_forward

And then start it or restart.  I like to restart to make sure everything is the way it needs to be before relying on it.  You could also just

# echo 0 > /proc/sys/net/ipv4/ip_forward

LXC Config

Really the only other thing you need to do is add a bit to /etc/lxc/default.conf.  This worked for me:

root@slacks:~# cat /etc/lxc/default.conf
lxc.network.type=veth
lxc.network.link=br0
lxc.network.flags=up

ON THE LXC GUEST

Just run netconfig and set a static address or DHCP and then restart rc.inet1.  

WHAT LXC GUEST?!!

Oh, I skipped that bit, eh?  Super simple.  Try this:
  
# lxc-create -n lxcguest -t /usr/share/lxc/templates/lxc-slackware
# lxc-start -n lxcguest -d
# lxc-console -n lxcguest  (it'll tell you how to login)

Now, run netconfig.  

What?!  You're already running Slackware on the host and you'd like to try something different?  Just run list the contents of  /usr/share/lxc/templates and then try one or a dozen of the other 18 pre-installed templates.  Like:

root@slacks:~# ls /usr/share/lxc/templates
lxc-alpine*     lxc-cirros*    lxc-openmandriva*  lxc-sparclinux*
lxc-altlinux*   lxc-debian*    lxc-opensuse*      lxc-sshd*
lxc-archlinux*  lxc-download*  lxc-oracle*        lxc-ubuntu*
lxc-busybox*    lxc-fedora*    lxc-plamo*         lxc-ubuntu-cloud*
lxc-centos*     lxc-gentoo*    lxc-slackware*


If you down like any of those, try something else with this command:

# lxc-create -t /usr/share/lxc/templates/lxc-download -n newguest

You will be given an even bigger choice.  Knowing Slackware and how stable it is, I would stay with the local choices to ensure that legendary stability stays as is (but that's just me). 

THE END

Well, that's all of my notes.  Postive comments and any kind of experiences with LXC are always welcome below.  

It's a good time to be a Linux sysadmin!

Linux is everywhere now.  It's on my TV, on my Roku, it's the firmware running my SAN hardware, it's the OS behind all of our virtualization platforms. If you know me, you know my technology passions are for Linux, Perl and pretty much anything running open source.  I started using Linux about 1993/94 when I downloaded SLS from GEnie over my 2400 baud modem.  It was kernel 0.99p11.  It booted Linux and ran off of floppy.  Later, I got a larger copy from GEnie using work's 9600 baud connection.  I had to dialup Indy to get a speed that fast!

Later, when Windows 95 came out, I started running Linux as my desktop and I've stuck with it.  I remember that the guys in my office would always reboot their Windows 95 systems at lunch as a preventative measure to prevent accidental lockups.  One time, just prior to lunch, I distinctly remember Ken yelling "Oh  no!  It locked up and I've been working on that spreadsheet for an hour!" I typed "w" to get my uptime:

[rat@localhost Desktop]$ w
 16:39:19 up 99 days,  8:14,  4 users,  load average: 0.25, 0.25, 0.27


Ha!  They can't keep their desktop up half a day - mine's been up for 99 days and still going.  I think to myself: "Linux - I think I'll keep it."

It's been over 20 years.  I can remember telling someone I worked on Unix and Linux systems.  "Ah, a niche OS, eh?"  "Niche?"  Not really.  Unix/Linux was running the Internet before these guys knew there was an Internet.  It's always been the one to run DNS, web servers, DCHP servers, NTP (time protocol), etc.  It ran all the SMTP (mail) and SNMP (network and hardware monitoring).  Linux WAS the back office of any decent sized IT shop. 

Later, Apple forked BSD Unix into its operating system OSX.  Now Apple was Unix!  I was very much at home on the Apple OSX command line.  Everything was there: Bash shell, Perl, and all the core Unix commands.  Pretty cool. 

Next came Windows PowerShell.  So many of the commands were aliased to bash commands that I was once again at home.  I really like Windows 2012 R2 Core and PowerShell.  Each new version of PowerShell adds more and more bash-like aliases.

And now, Microsoft Azure Cloud Services has dozens of versions of Linux you can deploy in their cloud service.  One estimate was that over 75% of the virtual machines in Microsoft Azure Cloud Service were Linux.  Even better - Microsoft runs AZURE on Linux!!  What's more, the Azure services SDK client also runs on Linux!  It was pretty freaky seeing bash scripts with a Microsoft license boiler plate on them.  And now the Office 360 is coming to Linux!

It's not a niche!  It's not going away.  I'd say that, without fan fare, Linus' OS has finally won.  I saw the future 20 years ago.  It is Linux!!

Merry Christmas everyone!

P.S. Don't forget - Linux is the OS running Android phones and the Raspberry Pi.

References:
http://www.wired.com/2015/09/microsoft-using-linux-run-cloud/

Slackware 14 under Xen

I have tried (halfway) to get Slackware to run under Xen (which I run on 32 bit CentOS 5.x).  It never seems to have a working network.  This time, I took a (very) little amount of time to fix this.  Googling resulting only in running Xen on Slackware.  I couldn't find anything on this problem.  I love to load each new distro that comes out but I really enjoy just using Slackware (SLS was my first distro).  So, when Slackware would repeatedly come up without a network interface, I was disappointed and a bit surprised.  If you're having this issue - here one possible fix:   Use a virtual Ethernet and do NOT use the default hypervisor network interface.  Instead, use "ne2k_pci".  I intend to try to get the shared physical interface to work with a real outside address and even test the other options under the virtual Ethernet.  But, this solved my problem.  If anyone else tries these, I'd love the hear the results.

I can't believe this actually worked!

I'm using Slackware 13 with XFCE. Love how fast and stable it is! But, I'm not much of a KDE fan. Especially KOffice - yuckko! So, I tried to install OpenOffice. It wouldn't compile due to some missing libraries and with the way Slackware is, getting the dependencies looked hopeless. Then I ran across this link: How do I install OpenOffice.org on Slackware? It was for OO 2 but I tried it anyway. I unpacked the OO 3 tar.gz, changed into the RPMS dir anbd ran the Slackware "rpm2tgz" tool. Then, unlike the instructions, I went crazy and just ran "pkgtool" on the whole directory. And it worked! So far, so good. No instabilities - but I'll post a reply to this if it blows up. Wish me luck!

New Linux

I've gotten spoiled by Ubuntu.  I think it's a great desktop OS (if you're into Linux).  I was recently using Fedora 11 as a Desktop at home (off of a bootable USBish device).  It's okay - I prefer it for server apps that are designed for Fedora.  I also loaded CentOS in a zone on  Solaris.  It's okay too.  Still - Ubuntu makes a lot of things too easy to pass up.  I've got Karmic Koala at home.  It's fine.  Can't see any difference between that and the 9.04 (whatever fuzzy animal that was named after - Feisty Fawn?)

Anyway, this guy was beating it up.  His reasons seem silly.  He's probably just trying to get some hits on his web site.

But I ran across this: Hadn't seen Lubuntu before (but noticed Knoppix's been using that desktop for a while). (I'm on Linux-Mag's mailing list since I *had* to see the answer to a forum there the other day).

So anyway, lot's of fanfare about Karmic this week.  This guy mentions ArchLinux as an easier alternative to Gentoo.  I wondered if anyone had tried it.  Then I remembered we had this mailing
list... but it bounced.  Maybe we don't have a mailing list anymore...

Hazzards of foreign language study

I was searching for the program schedule for Dish networks new (cheapest) Russian ala cart programming: ТВ-1000 Русское кино (TV1000 RUSSIAN KINO). Searching in English did not bear fruit so I switched my keyboard layout to Russian and searched. I found what I was looking for! A nice program schedule which also had movie descriptions (in Russian). I then got busy with other things and forgot about my PC.

When I came back to my desk, I was unable to unlock my keyboard. Again and again I tried, carefully typing my password and making note of the caps lock key indicator. Caps lock is off and I am typing it correctly: "I've been hacked!!" That always pops into my mind when this sort of thing happens. "No, no." I tell myself. "Don't jump to conclusions. That has never turned out to be the case in any of these situations." Then I notice: the keyboard layout is set to Russian! I'll NEVER be able to enter my password with a Russian keyboard layout. Что делать?!

I Googled for a possible hot key to toggle the keyboard layout (you can do this at the desktop - but in the screen lock position?) No luck. Then it occurred to be to use on of the pseudo tty terminals (I use Ubuntu Linux). Yup! Got in and killed off the screen saver and then toggled off the Russian keyboard layout. Whew!