Recently on my Linux Mint 13.2 system I was playing with Virtualbox. I wanted to pass through a USB device to a virtualbox VM but despite installing the appropriate extension pack, I was greeted with this lovely message in the USB menu:
No USB devices connected
I discovered here that you need to be a member of the vboxusers group. One quick command solved this:
sudo usermod -a -G vboxusers <username>
Once I did that I logged out and logged back in. Voila! USB passthrough worked.
It all started with an innocent enough e-mail:
Data Disk is filling up - please check. Current usage: 100%
I couldn’t find any clear information about what to do about this on Sophos’ forums. My data disk was full. What to do?
I can tell you what not to do – delete random files. I thought my solution would be to log into the UTM’s console and run a du -hsx /* to see where the space was. I found a large folder inside /var/storage – /var/storage/cores/httpd.16438. I removed it, because why not?
It turns out that did some weird things to my UTM. After removing that folder I kept getting spammed with these e-mails, once every hour:
Pop3 proxy not running - restarted
It took me a while to realize, but this also meant all e-mails relayed to the UTM were not being delivered. The entire POP/SMTP subsystem of the Sophos UTM was hosed. I could not find anything on the Sophos forums. After scratching my head I decided to have a deeper look at the logs. From the command line I issued
ls -ltr /var/log
and began reading the most recent logs.
pop3.log let me know what the problem was:
pop3proxy[9270]: Can't connect to database, retrying in 10 seconds: could not connect to server: Connection refused
I could not find any useful fixes for this error. I kept digging.
selfmon.log wasn’t much help other than to confirm that pop3 was having some serious issues. It was an endless abyss of repeated error messages:
selfmonng[3818]: W NOTIFYEVENT Name=pop3proxy_running Level=INFO Id=117 suppressed ... selfmonng[3818]: W actionCmd(+): '/var/mdw/scripts/pop3 restart'
system.log put me on the right track:
ulogd[5107]: pg1: connect: could not connect to server: No such file or directory
Finally, we’re getting somewhere! After some searching I learned that pg1 is the postgresql database Sophos uses. I found a way to rebuild from this forum post.
One simple command did the trick:
/etc/init.d/postgresql92 rebuild
This rebuilt the postgresql database that I apparently corrupted when I removed files with reckless abandon. My e-mails work again!
I am really enjoying my Chromebook Pixel 2015. Recently I needed to spin up a few VMs on this box. I tried to install virtualbox but it turns out that the kernel for the chromebook does not include virtualbox headers. Fortunately it’s fairly easy to add them, thanks to divx118’s scripts.
First, enable the necessary chromebook kernel flags. Run these commands in a crosh shell (not in a chroot)
cd ~/Downloads
wget https://raw.githubusercontent.com/divx118/crouton-packages/master/change-kernel-flags
sudo sh ~/Downloads/change-kernel-flagsNote: You will need to repeat the above steps after each chromeos update.
Next, open up a chroot shell and do the following:
cd ~
wget https://raw.githubusercontent.com/divx118/crouton-packages/master/setup-headers.sh
sudo sh setup-headers.shLastly, reboot the chromebook. Once you’re back up, enter your chrooted environment and install Virtualbox from their Oracle’s download page. Don’t use the virtualbox repositories – they don’t work.
Install the downloaded deb file with dpkg
dpkg -i virtualbox-5.0_5.0.10-104061~Ubuntu~trusty_amd64.deb
You might get this error:
dpkg: dependency problems prevent configuration of virtualbox-5.0: virtualbox-5.0 depends on libqt4-opengl (>= 4:4.7.2); however: Package libqt4-opengl is not installed.
The fix to that error is to run the following command to install missing dependencies:
apt-get -f install
If you get weird errors about VT-X not being enabled in the BIOS, try running the script and rebooting again.
Success!
I recently needed to re-install my Owncloud VM. I’ve been on a CentOS kick lately so I decided to see if I could install OwnCloud 8 on a Centos 7 base install. It turned out to not be as easy as I thought it would be.
When I tried to install owncloud on my CentOS 7 system, I kept getting a 404 error message even though I followed the documentation outlined here.
It turns out that they changed where the RPM is held and apparently forgot to update the documentation. I discovered this by manually navigating to download.suse.org/repositories/isv:ownCloud:community and browsing the directories. The documentation has you grab a repo from Centos_Centos-7 folder, which is broken. It looks like the proper directory is just Centos_7.
I had to remove the old repo, purge the cache, and try again. To do so, remove the .repo file and purge via yum:
cd /etc/yum.repos/d/ rm isv\:ownCloud\:community.repo yum --enablerepo=isv_ownCloud_community clean metadata wget http://download.opensuse.org/repositories/isv:ownCloud:community/CentOS_7/isv:ownCloud:community.repo yum install owncloud
The above procedure is what you should run if you’ve already tried to use the broken link in the documentation and failed. If you haven’t installed owncloud yet, do the following
cd /etc/yum.repos/d/ wget http://download.opensuse.org/repositories/isv:ownCloud:community/CentOS_7/isv:ownCloud:community.repo yum install owncloud
Success.
After configuring a software RAID to host my VMs on my Xenserver 6.5 instance I began receiving odd e-mails once a week. The e-mails simply said:
/usr/sbin/raid-check: line 62: declare: -A: invalid option declare: usage: declare [-afFirtx] [-p] [name[=value] ...]
It turns out /usr/sbin-raid-check is a bash script called from the file /etc/cron.d/raid-check. It’s a weekly cron job designed to “scrub” the RAID array. I was getting these e-mails because I had configured my xen server to e-mail me anything sent to root, which includes messages encountered during cron jobs.
There appears to be a typo in the raid-check script. Line 62 of raid-check reads:
declare -A check
After reading the syntax of the declare command, I believe the issue is the fact that the A is capitalized. I commented out that line and replaced it with
declare -a check
That seemed to work. No more weird errors coming from my xenserver.
I do this infrequently enough that I decided I should really write this down. Below is the quick and dirty way to get the Splunk universal forwarder installed on a new Linux system. Thanks to byteschef for the information used to create this guide.
Download the latest splunk .RPM from their site and install it via RPM -i <filename> (if RedHat based) or dpki -i <filename> if debian based.
Run the following commands as root:
cd /opt/splunkforwarder/bin ./splunk start --accept-license ./splunk enable boot-start ./splunk add forward-server <IP/hostname of splunk server>:9997 -auth admin:changeme ./splunk add monitor /var/log ./splunk edit user admin -password NEW_PASSWORD -auth admin:changeme ./splunk restart
If there are any other directories you want monitored other than /var/log (application logs, for example) then issue:
./splunk add monitor <directory to monitor>
Done.
It never seems to go smoothly, does it? I just upgraded my version of Owncloud from 8.0.4 to 8.1.1 on my Ubuntu Trusty Tahr 14.04 VM. After the upgrade I noticed that all my samba (SMB) shares were gone. The logs were not very helpful, full of things like these:
Exception: {"Exception":"Icewind\\SMB\\Exception\\InvalidHostException","Message":"","Code":0,"Trace":"#0 \/var\/www\/owncloud\/apps\/files_external\/3rdparty\/icewind\/smb\/src\/Connection.php(37): Icewind\\SMB\\Connection
Additionally errors like this were showing up:
Your web server is not yet set up properly to allow file synchronization because the WebDAV interface seems to be broken.
After much digging I discovered this post which had a suggestion to install libsmbclient-php. In Ubuntu 14.04 it involves this command:
sudo apt-get install php5-libsmbclient
That did the trick! After installing php5-libsmbclient my samba shares worked once more.
The FreeBSD ports tree is wonderful for installing software but sometimes it can be a real pain. Recently I was trying to install Emby in FreeBSD because why not? The instructions were easy enough except for when I ran
make install clean
I was constantly barraged with choices for things. I want to assume the default on all of these and not be barraged with questions.
Thanks to stack exchange I learned it’s relatively easy to bypass all these questions. Simply add:
BATCH=yes
to the end of your make install clean statement to assume the defaults to all the questions for the package. The Emby guide is pretty comprehensive, but I would add this command at the bottom:
make install clean BATCH=yes
Handy.
After tethering my phone to my laptop and googling “what is my ip” I was surprised to find an IPv6 address. Apparently my mobile carrier has implemented IPv6. Bravo to them.
Unfortunately, when I initiated my VPN, which is supposed to tunnel all traffic through it, my IP address didn’t change. This is because my VPN is IPv4 only. My system prioritizes IPv6 traffic, so if I happen to go to any IPv6 enabled site such as google, my VPN tunnel is bypassed entirely.
I don’t like the security implications of this. The long term solution is to implement IPv6 with my VPN; however while traveling I won’t be able to do that. The short term solution is to simply disable IPv6 for the interface that has it, in my case usb0 as that is what is tethered to my phone.
This simple command will do the trick:
sudo sh -c 'echo 1 > /proc/sys/net/ipv6/conf/usb0/disable_ipv6'
Change USB0 to whatever interface you would like (or all of them) and you’re done! Thanks to this site for the information.
I really love using Crouton on my Chromebook Pixel LS 2015. I was sad to see that there is no cinnamon desktop environment target with the latest versions of crouton. Below is what I did to get Cinnamon on my chromebook. Much of what I did was taken from https://gist.github.com/sohjsolwin/5939948
sudo apt-get update sudo apt-get install software-properties-common python-software-properties sudo add-apt-repository ppa:tsvetko.tsvetkov/cinnamon sudo apt-get update sudo apt-get install cinnamon
Once Cinnamon was installed I needed to know how to start it manually. Thanks to the Arch Linux forums for explaining it. You have to create a .xinitrc file in your home directory within your chroot.
echo "exec cinnamon-session" > ~/.xinitrc
Trying to manually start cinnamon by typing startx didn’t work – I got a blank screen and had to hard reset to get anything to come back. Thanks to github I learned you need to use xinit instead of startx.
Lastly, we need to create a suitable startcinnamon script.
wget https://gist.github.com/sohjsolwin/5934362/raw/f68fc0942798902a0bd48f40c17dc0cd5cf585ea/startcinnamon
Modify the file to remove the startx command with xinit. Also remove everything after xinit. My file is as follows:
APPLICATION="${0##*/}"
USAGE="$APPLICATION [options]
Wraps enter-chroot to start a Mint session.
By default, it will log into the primary user on the first chroot found.
Options are directly passed to enter-chroot; run enter-chroot to list them."
exec sh -e "`dirname "$0"`/enter-chroot" "$@" xinit
Make this file executable (chmod +x startcinnamon) and move it to the /usr/local/bin directory of your chromebook (not your chroot.) Now all you need to do is enter
sudo startcinnamon
and your cinnamon desktop should come up!
Update 2016-01-04
These two scripts seem to work a little bit better. Place this one within your chroot under /usr/local/bin/startcinnamon:
#!/bin/sh -e # Copyright (c) 2015 The crouton Authors. All rights reserved. # Use of this source code is governed by a BSD-style license that can be # found in the LICENSE file. # Launches GNOME; automatically falls back to gnome-panel exec crouton-noroot gnome-session-wrapper cinnamon
Place this one in /usr/local/bin outside your chroot (on your chromebook itself.)
#!/bin/sh -e
# Copyright (c) 2015 The crouton Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
set -e
APPLICATION="${0##*/}"
USAGE="$APPLICATION [options]
Wraps enter-chroot to start a GNOME session.
By default, it will log into the primary user on the first chroot found.
Options are directly passed to enter-chroot; run enter-chroot to list them."
exec sh -e "`dirname "\`readlink -f "$0"\`"`/enter-chroot" -t cinnamon "$@" "" \
exec startcinnamon