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If you start a VPS and it gives the following error:

vzquota : (error) Quota on syscall for 100: Device or resource busy

Running vzquota on failed for VPS 100 [3]

Then it means that there are some open files from that VPS. Please make sure there are no open files inside VPS root and/or private area (and your current working directory is not inside VPS root/private area) by running the following command on the hardware node:

lsof 2> /dev/null | egrep ‘/vz/root/VPSID|/vz/private/VPSID’

If there are any processes which hold a directory inside VPS root/private area - kill them.

e.g:

[root@server ~]# vzctl start 100

Starting VPS …
vzquota : (error) Quota on syscall for 100: Device or resource busy
Running vzquota on failed for VPS 100 [3]

[root@server ~]# lsof 2> /dev/null | egrep ‘/vz/root/100|/vz/private/100′

tar 11101 root 9r REG 8,5 41995369 457695234 /vz/private/100/root/home/username/mail/inbox

[root@server ~]# kill -9 11101

[root@server ~]# vzctl start 100
Starting VPS …
VPS is mounted
Adding IP address(es): 192.168.1.1
Hostname for VPS set: vps.servername.com
File resolv.conf was modified
Setting devperms 60010 dev 0×22
VPS start in progress…

The Plesk admin password can simply be reset by login to VPS using RDP with following command:

%plesk_bin%\plesksrvclient.exe

Just run the command and it will ask for new admin password. If it also shows the message that Access denied/can’t connect to MySQL then:

1. Add parameter skip_grant_tables=1 into the [PleskSQLServer] section.
2. Restart service Plesk SQL Server.

%plesk_bin%\plesksrvclient.exe -get command can be used to retrieve the Plesk admin password from the database to verify that the password has been successfully updated in Plesk system database. If Plesk admin password is not updated somehow then it can be updated manually. To do it, please, follow the steps:

1. Edit MySQL configuration file my.ini located within %plesk_dir%\mysql\data\.
2. Add parameter skip_grant_tables=1 into the [PleskSQLServer] section.
3. Restart service Plesk SQL Server.
4. Log into Plesk MySQL.

%plesk_dir%\mysql\bin\mysql.exe -P8306 mysql

1. Execute the following query:

mysql> update mysql.user set password=password(’NEWPASSWORD’) where user=’admin’;

1. Remove skip_grant_tables=1 from within the [PleskSQLServer] section within %plesk_dir%\mysql\data\my.ini
2. Restart service Plesk SQL Server.

Cert installed in the service VE is the cert used by VZPP and VZCC and it is located at:

/etc/httpd/conf/ssl.crt/server.crt
/etc/httpd/conf/ssl.key/server.key

You need to enter to Service VE from the Hardware Node to update these certificate files as “

vzctl enter 1

After renewing the certificate, VZCP service needs to be restarted :

/etc/init.d/vzcp restart

VPS can have either metered bandwidth at higher rate like 100Mbps port or unmetered at a lower rate like 2Mbps, 3 Mbps etc depending on the plan.

This can be done from vzmc :

Got to Properties of VPS > Traffic Shapping

For Unmetered :

Open the Class 1 named file and add respective value ,

e.g. 1024 for discovery plan > i.e. 1Mbps, and 2048 for freedom i.e. 2 Mbps and so on.

And Check the ‘Check Box’ below named ‘Rate Guarantee is also a bound’

For Metered :

Open the Class 1 named file and enter 102400 in it.

Uncheck the check box below named ‘Rate Guarantee is also a bound’

If you do a “yum update” inside Linux VPS and get this error:

Package glibc-dummy-centos-3 needs glibc-common = 2.3.2-95.30, this is not available.

Then on the VPS do

rpm –qa | grep glibc

it will list the glibc rpms installed on the VPS, look for an rpm glibc-dummy-centos-3 and erase it by

yum erase glibc-dummy-centos-3

glibc-dummy-centos-3 is developed by swsoft. glibc postinstall scripts create a 30-mb big
file /usr/lib/locale/locale-archive.

The only purpose of this glibc-dummy-centos-3 package is to move the file to the template area in order to save 30MB of disk space per every centos-3 based VPS. It is save to deinstall this package from a VPS before upgrading glibc.

On all the VPSs the iptables modules are not enabled by default , and usually client get below error in this case :

“iptables v1.2.8: can’t initialize iptables table `filter’: Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.”

The iptable modules can be enabled through shell or vzmc , through vzmc you can simply select the modules , press enable and the vps will get restarted and the iptables modules will be enabled. Before enabling iptables on VPS, it needs to make sure that the iptables modules are enabled on the Hardware Node. In order to enable iptables modules on Hardware Node, edit /etc/sysconfig/iptables-config file on a Virtuozzo hardware node and look for the following parameter value:

IPTABLES_MODULES=”ipt_REJECT ipt_tos ipt_TOS ipt_LOG ip_conntrack ipt_limit ipt_multiport iptable_filter iptable_mangle ipt_TCPMSS ipt_tcpmss ipt_ttl ipt_length ipt_state iptable_nat ip_nat_ftp”

Also edit /etc/sysconfig/vz file on a hardware node and look for the following parameter value:

IPTABLES=”ipt_REJECT ipt_tos ipt_TOS ipt_LOG ip_conntrack ipt_limit ipt_multiport iptable_filter iptable_mangle ipt_TCPMSS ipt_tcpmss ipt_ttl ipt_length ipt_state iptable_nat ip_nat_ftp”

Next step would be enabling iptables modules on VPS. This is how we can do it:

VEID=XXX (where XXX is the actual VPS ID that can be checked using “vzlist -a” command)

vzctl stop $VEID ; vzctl set $VEID –iptables ipt_REJECT –iptables ipt_tos –iptables ipt_TOS –iptables ipt_LOG –iptables ip_conntrack –iptables ipt_limit –iptables ipt_multiport –iptables iptable_filter –iptables iptable_mangle –iptables ipt_TCPMSS –iptables ipt_tcpmss –iptables ipt_ttl –iptables ipt_length   –iptables ipt_state –iptables iptable_nat –iptables ip_nat_ftp –save

vzctl set $VEID –numiptent 2000 –save

vzctl start $VEID

Virtuozzo VPS is composed of several parameters that are called QOS Parameters. These parameters define all the resources i.e disk space, memory, cpu, disk inodes etc for that VPS.  The parameters are defined inside VPS configuration file. A file /proc/user_beancounters inside the VPS contains the real time usage figures for these parameters. RAM statistics can be calculated for any Virtuozzo Linux VPS using these Formulas:

Guaranteed memory = barrier of vmguarpages / 1024 * 4
Burstable memory = privvmpages / 1024 x 4
Current Memory Usage= physpages held value /1024 * 4
Current Usage (RAM + SWAP)= oomguarpages held value /1024 * 4

In Windows Virtuozzo, all Windows upgrades need to be installed on Hardware Node instead of VPS. If  Windows upgrades will be installed inside VPS and those upgrades are not installed on Hardware Node, the VPS will be corrupted and it won’t start up on reboot. In thie case, all system files in system32 and system32\drivers folder need to be replaced with the system files from Hardware Node to start the VPS. These commands can be used to replace the system files inside VPS.

copy /y  C:\WINDOWS\system32  C:\vz\root\VE_ID\C\WINDOWS\system32
copy /y  C:\WINDOWS\system32\drivers  C:\vz\root\VE_ID\C\WINDOWS\system32\drivers

(NOTE: Replace System Drives and path as per the installation)

In Virtuozzo 3, vzagent0 user was used to connect to VZMC (Virtuozzo Management Console). As a regular practice passwords are changed so after resetting vzagent0 password, its recommended to clear the SSH authorized keys too. Following commands can be used to clear the SSH authorized keys for vzagent0.

On Linux Nodes:

vzctl exec 1 “> /home/vzagent0/.ssh/authorized_keys2″

on Windows Nodes:

vzctl exec 1 cmd /c del “c:\Program Files\OpenSSH\home\vzagent0\.ssh\authorized_keys2″

Virtuozzo Power Panel allows the Full VPS backup to be generated but the number of allowed backups is limited. Number of backups is defined on the HW node and used for all VPSs. For example two different VPSs on the same node couldn’t have different number of backups.

You could set number of backups by the following ways:

1. In the file - /etc/sysconfig/vzagent/vzagent.conf you should change the following string:

<pe_backups_limit>1</pe_backups_limit>

and restart vzagent - vzagent_ctl restart

2. In the VZMC:

Select Virtuozzo node > Tasks > Manage VZAgent Configuration > backm > configuration > pe_backups_limit