OpenVPN issues on a OpenVZ / Virtuozzo enabled VPS

Error Note: Cannot open TUN/TAP dev /dev/net/tun: Permission denied (errno=13)

Just follow the KB at http://wiki.openvz.org/VPN_via_the_TUN/TAP_device

Error Note: Cannot set tx queue length on tun0: Operation not permitted (errno=1)

As mentioned in the same KB URL, just do the steps below and things should be alright again

vzctl set 101 --devices c:10:200:rw --save
vzctl set 101 --capability net_admin:on --save

Basically the errors are caused by the non-execution of the two commands mentioned above.

User stats in directadmin admin area – Solved with a good client’s help :)

When one of our clients, Mr. Xavier opened an issue with us regarding the Usage stats not being shown, we were certain that this is a bug with DirectAdmin in the way how its license are read. We changed the ethernet_dev in directadmin.conf, but that didn’t work out.

Client was asking us,

In Admin Area –> Complete Usage Statistics –> Usage stats for venet0:0 is showing “None”

It’s possible to fix this to reflect the traffic of this virtual adapter?

DirectAdmin didn’t give a direct solution. Instead provided us with a complete packed files related to DirectAdmin. So the solution was this.

cd /usr/local/directadmin
wget -O new.tar.gz http://files.directadmin.com/7694310/packed_es50.tar.gz
tar xvzf new.tar.gz
./directadmin p
killall -9 directadmin
./directadmin d
/etc/init.d/directadmin restart


For anyone facing this issue. I didn’t check more deeper into what changed, but must be related to htmls in data page on how device gets read.

Adding packages from WHM or editing the reseller privileges is not working on a x86_64 architecture

As usual, start by checking the error log of cPanel at /usr/local/cpanel/logs/error_log

2009-05-23 15:44:24 info [whostmgr2] [28346] Waiting for lock on /var/cpanel/package-limits.yaml held by /usr/local/cpanel/whostmgr/bin/whostmgr2 – locking /var/cpanel/package-limits.yaml with pid 25968
2009-05-23 15:44:25 info [whostmgr2] [28346] Removing expired lock file /var/cpanel/package-limits.yaml.lock
(internal warning while parsing [stdin]) Sat May 23 23:41:28 2009 [25968] warn: Attempt to free unreferenced scalar.

While the error (internal warning while parsing [stdin]) Sat May 23 23:41:28 2009 [25968] warn: Attempt to free unreferenced scalar floods the error log

Permissions were all right, but suddenly this started happening, but only x86_64 architectures only. Reason being the cPanel is killing the process, since it exceeded the memory usage allowed by cPanel.

Solution would be to increase the memory limit of cPanel by following the instructions below.

WHM -> Server Configuration -> Tweak Settings Choose the setting for:

The maximum memory a cPanel process can use before it is killed off (in megabytes). Values less than 128 megabytes can not be specified. A value of “0″ will disable the memory limits.

The settings had 256M there, and increasing the value to 1024 M helped. Server had 8G RAM, so the value of 1024M was fine here.

How do I reset the root mysql pass, lxadmin created ?

Oh, do it from the GUI lxadmin gives you OR else, do it console based way.

# cd /usr/local/lxlabs/lxadmin/httpdocs/
# lphp.exe ../bin/common/misc/reset-mysql-root-password.phps

Server refused to allocate pty in a VPS & CentOS 5.3

With CentOS 5.3 released on 1st April of this year, more udev related issues crops in. I don’t know when OpenVZ will get better in its thinking. Issue is there in every VPS who has got the udev upgraded as a result of no excludes in yum.conf entries. Two solutions exists as per http://wiki.openvz.org/Container_enter_failed

Editing the rc.sysinit is the solution which will work here. But when I explained to one of our customers that we edited rc.sysinit, he thought it is /etc/rc.sysinit in the node. Be warned : Don’t do that! Instead from the node edit the etc/sysinit of the VPS, like vi /vz/private/VPSID/etc/rc.sysinit.

However the proper solution, we believe is to

yum remove udev

go ahead with yes to remove dependencies as well. It will also remove ImageMagick, which you have to later install it manually from source. Follow the how to for the installation of ImageMagick below, since the yum based installation of ImageMagick has dependency on hal and udev packages.

/me wonders why are they dependent though..

yum install ghostscript
wget ftp://ftp.imagemagick.org/pub/ImageMagick/ImageMagick.tar.gz
tar xvzf ImageMagick.tar.gz
rm -rf ImageMagick.tar.gz
cd ImageMagick*
./configure –enable-shared –with-modules  –with-freetype=yes –with-gs-font-dir=default –with-perl=yes –with-xml=yes –with-zlib=yes –with-jpeg=yes –with-png=yes –without-x
make
make install

After the udev is removed, edit the /etc/yum.conf and make sure that the exclude= line has udev* mkinitrd module-init-tools and kernel* added to it. cPanel usually adds kernel*, but I guess its our responsibility to add udev* in a VPS, till cPanel’s upcp does it for us in a VPS