Author Archives: Vyacheslav

Configuring Loopback Detection on Alcatel OS-LS 6200

For example, configure Loopback Detection on the Alcatel OmniStack LS 6224 switch.

Let’s look at the current settings for Loopback Detection:

enable
show loopback-detection

Let’s go into the configuration mode, enable and specify some parameters of Loopback Detection:

configure
loopback-detection enable
loopback-detection mode src-mac-addr
loopback-detection interval 30

Turn on the client ports Loopback Detection:

interface range ethernet e1-24,g2-4
loopback-detection enable
exit

g1 I have an uplink, so I did not enable Loopback Detection on it.

Let’s configure automatic activation of the port after 3000 seconds, if it was turned off due to the loop (you can specify the value in seconds 30-86400, standard 300):

errdisable recovery interval 3000
errdisable recovery cause loopack-detection
show errdisable recovery
show errdisable interfaces

Exit the configuration mode and save the configuration:

exit
copy running-config startup-config

Configuring the Alcatel OmniStack LS 6224

By the way, console cable for Huawei and D-Link switches (for example S2326TP, DES-3200) did not approach the Alcatel OmniStack LS 6224, because it does not use the first contact.
When I assembled the working cable according to the scheme, it did not work through the Chinese USB-RS232 adapter, so I had to connect directly to the COM port of the computer.
The standard connection speed is 9600-8-N-1.

The circuit on which I assembled the cable:
1 – white-brown
2 – green
3 – white-green
4 – orange
5 – blue and white-blue
6-4 – jumper
7 – white-orange
8 – brown

Where the digits are RS-232, but I crimped the RJ45 according to the standard)

After connecting to the switch, we will switch to the mode of elevated privileges:

enable

Let’s look at the existing configuration:

show running-config
show startup-config

Now go into the configuration mode:

configure

Continue reading “Configuring the Alcatel OmniStack LS 6224”

How to crimp a twisted pair connector RJ45 / 8P8C

Crimping the connector is carried out with a special crimping tool (crimping pliers), in extreme cases if they are not available you can use a flat thin screwdriver. First carefully remove the 3 centimeters of the upper braid cable, weave pairs of conductors and align in a row according to the standard that we need. Superfluous ends cut off to about 1cm remained. We put it into the connector so that the conductors have reached the very end of the connector and have rested, the outer insulation of the cable should also as far as possible go into the connector. We check that the colors are not messed up when inserting, we insert it into the crimper and squeeze. Done.

Twisted pair crimp standards:
1) direct link, the most used, is often used to connect a computer with a switch, a router, etc. Both connectors are crimped the same way.
white-orange / orange / white-green / blue / white-blue / green / white-brown / brown

rj45

2) cross-link, it is used to connect two computers to each other, but in our time computers can be connected and the cable is compressed by the standard above, so it is used quite rarely. One connector is crimped as indicated below, the second as indicated above.
white-green / green / white-orange / blue / white-blue / orange / white-brown / brown

The solution of the “System error 1231 has occurred” when connecting a network drive

I once needed to connect a network drive to make a backup copy of the system, but an error occurred when I executed the connection command:

C:\Users\Administrator>net use K:\\192.168.0.5\dir /persistent:no /user:name password
System error 1231 has occurred.
The network location cannot be reached. For information about network troublesho
oting, see Windows Help.

Later I determined that in the connection properties on the local network (also called Ethernet and Local Area Connection), the checkboxes for “Client for Microsoft Networks” and “File and Printer Sharing for Microsoft Networks” were removed.

After I ticked these components and applied, the disk successfully connected:

C:\Users\Administrator>net use K:\\192.168.0.5\dir /persistent:no /user:name password
The command completed successfully.

Error 1231 can also be displayed if, for example, the Netbios ports are blocked on the firewall or on the provider’s equipment so that users do not see the shared disks.

See also my article – Installing and Configuring Samba on Linux

Solving the problem of resetting the contrast after upgrading Windows 10

Once my Windows 10 installed another update, at the end of 2017, I did not remember which version the update was made on.
Immediately after the update, the computer rebooted and at startup I noticed that the screen became darker, the contrast increased, the black color became really black, almost like on Apple devices, but in fact the colors became not natural and it was not really possible to work with graphics.
For the test, I ran a few games and noticed that when moving a character to CS:GO for example, on some maps, the chart becomes so dark that you can forget about the game.
At that time, the Asus GeForce GTX 1060 Dual 6GB video card was installed on the computer, tried to switch color profiles in the NVIDIA panel, auto contrast correction turned off, but after restarting the computer the problem appeared again.
After I pulled out the video card, the integrated Intel® HD Graphics 630 had the same problem and setting parameters in the panel did not help.
Updating drivers for both video cards did not work either.

As it turned out, along with the update, Microsoft added Calibration Loader to the autorun via Task Scheduler, it just spoiled everything.

To solve the problem, I disabled it in the task scheduler.

You can find the “Calibration Loader” by clicking “Start” – “Task Scheduler”, go to \Microsoft\Windows\WindowsColorSystem, where I saw:

Name: Calibration Loader
Location: \Microsoft\Windows\WindowsColorSystem
Author: Microsoft Corporation
Description: This task uses color calibration options.

In the “Triggers” tab, you must disable both the “Log on” and “When connecting to a user session” flip-flops. This can be done by selecting the trigger, clicking the “Change” button below and unchecking the “Enabled” checkbox.

After that, without the Calibration Loader everything began to be displayed well.

Install Apache JMeter in Ubuntu

Apache JMeter — load testing tool.

For Apache JMeter you need to install Java, see my article – Installing Java on Linux.

For an example I’ll install Apache JMeter in Ubuntu Desktop 18.04.

After Java is installed, copy the link to the archive with the latest version of Apache JMeter from the official site http://jmeter.apache.org/download_jmeter.cgi and download it:

wget http://apache.volia.net//jmeter/binaries/apache-jmeter-4.0.tgz

Extract the archive:

tar -xf apache-jmeter-4.0.tgz

Run:

cd apache-jmeter-4.0/bin/
./jmeter

After the startup, a message was displayed that you can create tests in the Apache JMeter graphical mode, and you can execute them only from the terminal, for example:

jmeter -n -t [jmx file] -l [results file] -e -o [Path to web report folder]

By the way, Apache JMeter in Windows is run through the jmeter.bat file.

Loading and Unloading Modules in Linux

In this article I will give an example of manual and automatic loading/unloading models in Linux.

First, switch to root user if not under it, for example in Ubuntu it can be done like this:

sudo -i

Let’s see a list of the downloaded modules:

lsmod

To see if a particular module has been loaded so it can (where NAME is the module name):

lsmod | grep NAME

The following commands are used to load/unload a module:

modprobe NAME
modprobe -r NAME

When the module load command is executed, modprobe looks for it in the directory:

/lib/modules/$(uname -r)

You can see what it is like:

ls /lib/modules/$(uname -r)
ls /lib/modules/$(uname -r)/kernel/net/netfilter/

To load/unload a module from another directory, you can execute the following commands:

insmod /path/to/module/name.ko
rmmod /path/to/module/name.ko

View information about the module and the possible startup parameters as follows:

modinfo NAME

You can see specific information about the module, for example, where it is located:

modinfo --filename NAME

In order for the modules to start at the very beginning of the system startup, they must be written to the /etc/modules.conf file, and in order to start last when all services are started, the file is /etc/rc.local.
In addition to the file /etc/modules.conf there is also a directory /etc/modprobe.d/, where there are similar files with the extension .conf.

For example, in rc.local modules are written like this:

/sbin/modprobe NAME

The modules.conf file is written like this:

nf_nat_ftp

To prevent the module from loading, you can write the word blacklist before the module name:

blacklist NAME

Installing the Webuzo Control Panel

For an example I’ll install the Webuzo control panel in Ubuntu 16.04 LTS.

Switch to the root user:

sudo -i

Download the installation script:

wget -N http://files.webuzo.com/install.sh

Make the script file executable:

chmod 0755 install.sh

Run the installation script:

./install.sh

We will wait until the installation is complete.
When the installation was complete, I had the following:

——————————————————–
Welcome to Webuzo Installer
——————————————————–
Installation Logs : tail -f /root/webuzo-install.log
——————————————————–
1) Installing Libraries and Dependencies
2) Setting UP WEBUZO
3) Downloading and Installing Webuzo
4) Downloading System Apps
—————————————————————-
/$$ /$$ /$$$$$$$$ /$$$$$$$ /$$ /$$ /$$$$$$$$ /$$$$$$
| $$ /$ | $$| $$_____/| $$__ $$| $$ | $$|_____ $$ /$$__ $$
| $$ /$$$| $$| $$ | $$ \ $$| $$ | $$ /$$/ | $$ \ $$
| $$/$$ $$ $$| $$$$$ | $$$$$$$ | $$ | $$ /$$/ | $$ | $$
| $$$$_ $$$$| $$__/ | $$__ $$| $$ | $$ /$$/ | $$ | $$
| $$$/ \ $$$| $$ | $$ \ $$| $$ | $$ /$$/ | $$ | $$
| $$/ \ $$| $$$$$$$$| $$$$$$$/| $$$$$$/ /$$$$$$$$| $$$$$$/
|__/ \__/|________/|_______/ \______/ |________/ \______/
—————————————————————-
Congratulations, Webuzo has been successfully installed
You can now configure Softaculous Webuzo at the following URL :
http://192.168.1.9:2004/
—————————————————————-
Thank you for choosing Webuzo !
—————————————————————-

After that I opened in the browser http://192.168.1.9:2004/, indicated the invented username and password, email and domain/IP name on which Webuzo will work.
This completes the installation and displays the following information:

You can login to the Webuzo Admin Panel using your root details at the following URL :
http://192.168.1.9:2004/
To start installing Apps you can login with the following details :
URL : http://192.168.1.9:2002/
Username : admin
Password : (the one you entered)
We request you to please register for updates and notifications at :
http://www.softaculous.com/board/index.php?act=register It also inspires us when you register. Registration is free and just a one minute job.
If you need any support you can always count on us. Just drop in at our Support Board:
http://www.webuzo.com/forums
Alternatively, you can contact us via Email at support@webuzo.com
Thank you for choosing Webuzo!

Since a free version of Webuzo is installed, many utilities and modules will become available only after upgrading to the premium version of Webuzo.