Category Archives: Hardware

Lenovo A3000 Hard Reset

On the test I will use Lenovo A3000-H.

Let’s get started. Turn off the tablet if it is possible, if not, we still press and hold the power key and the volume up key at the same time until the following menu appears:

Recovery Mode
Fastboot Mode
Normal Mode

Press the volume up key to select the desired mode, and go to the volume down key. In our case, let’s move on to Recovery Mode.

There was a robot, we put the power button on and another menu will appear. In it, on the contrary, by the sound reduction button we select the necessary operation, and the magnifications will be performed by it.
First we choose and execute “wipe cache partition“, later “wipe data/factory reset” and at the end we execute “reboot system now“, the device will reboot with standard settings and without user data.

Done.

Hard Reset Lenovo A390t

I will describe a few simple steps to perform a hard reset on the Lenovo A390t:

1) Turn off the device if it is turned on.
2) Press the volume button up and the power button simultaneously, wait for the Recovery menu to appear.
3) In the recovery menu, press the volume down/up button to highlight “Wipe data/factory reset” and select it by pressing the power button, then select “Wipe cache partion” in the same way.
4) When cleaning is complete, the recovery menu will appear again, in which we select “reboot system now“, after which the device will reboot.

Done.

HP Printers SNMP OID’s

On the test, I will use the HP LaserJet P2055dn printer.

Here is a list of tested OIDs for obtaining various SNMP information:
1.3.6.1.2.1.43.11.1.1.8.1.1 (Maximum number of copies of toner)
1.3.6.1.2.1.43.11.1.1.9.1.1 (Remaining number of copies of toner)
1.3.6.1.2.1.43.12.1.1.4.1.1 (Toner color)
1.3.6.1.2.1.43.10.2.1.4.1.1 (Number of pages printed)
1.3.6.1.2.1.43.5.1.1.17.1 (Serial number of the printer)

To see a list of all possible oid’s, you can run the command in Linux:

snmpwalk -v 1 -c public 192.168.24.112

You can check the specific oid with the command:

snmpget -v 2c -c public 192.168.24.112 1.3.6.1.2.1.43.11.1.1.9.1.1

Mikrotik SMB – file server configuration

I will use the Mikrotik RB951G-2HnD router as an example.

Connect the media to the USB router.
Let’s look at the status:

store disk print

Format it:

store disk format-drive 1

Reboot the router:

reboot

Add storage:

store add name=share disk=usb1 type=user-manager activate=yes comment="test"

Add share:

ip smb share add name=test max-sessions=15 directory=/test disabled=no comment="test share"

Example of disabling share:

ip smb share disable

Enabling smb:

enable smb

I will give examples of some commands:
ip smb print (view parameters)
ip smb set allow-guests yes/no (allows connection to guest users without entering a password, standard yes)
ip smb set comment TEXT (comment, standard MikrotikSMB)
ip smb set domain NAME (setting the name of the workgroup, standard MSHOME)
ip smb set enabled yes/no (SMB on/off, standard no)
ip smb set interfaces all/wlan1/bridge-local/… (installation of interfaces on which SMB will be started, standard all)

ip smb users add read-only=no name=LOGIN password=PASSWORD disabled=no (user creation)
ip smb users disable (disabling the user)
ip smb users enable (user activation)
ip smb users print (view the list of users)
ip smb users remove (deletion of the user)
ip smb users set read-only=no name=LOGIN password=PASSWORD (user change)

ip smb share enable
ip smb share print (view share list)
ip smb share remove
ip smb share set (changing the parameters of the share)

To get help, use the “?” character on the command line.
To go to the level above – “..”.

Example of configuring the firewall for smb:

add action=accept chain=input disabled=no dst-port=137-138 protocol=udp src-address-list=smb-allow
add action=accept chain=input disabled=no dst-port=137,139 protocol=tcp src-address-list=smb-allow
ip firewall address-list add address=1.1.1.1 disabled=no list=smb-allow

Official documentation:
wiki.mikrotik.com/wiki/Manual:IP/SMB
wiki.mikrotik.com/wiki/Manual:Store

You can also connect a hard drive to the router via the USB-SATA adapter.

Hard Reset Ergo A500 Best

In order to fully reset the settings on the Ergo A500 Best smartphone to the factory settings and erase the user data, perform several steps:

1) Turn off the device.

2) Press the Volume Up and Power Button simultaneously until the menu appears.

3) Press the Volume Up key to select “Recovery” and confirm the selection with the Volume Down key.
Should appear robot android.

4) Press the Volume Up and Power Button again at the same time.
The recovery menu should appear.

5) By the menu, you can move the volume up and down keys.
In this way, select “wipe data/factory reset” and confirm the selection with the power key.
In the next window, select “Yes – delete all user data” and confirm with the power key.
Let’s wait until the data is erased and the settings are reset.
At the end, in the same way, we select Reboot to reboot the device.

Done.

SNMP OIDs for the HP 5800 Switch

I’ll list some of the OIDs I used:
Determine the OID of the processor load by running the command in Linux:

snmpwalk -v 2c -c сommunity host .1.3.6.1.4.1.25506.2.6.1.1.1.1.6
snmpwalk -v 2c -c сommunity host .1.3.6.1.2.1.47.1.1.1.1.7

As a result of the execution of the first command, a list of OIDs will be displayed, those in which a value greater than 0 means CPU loading. If the switches are stacked, then the OID with a value greater than zero will be greater than one. The second team is looking at the description, ours will be “Board”.

Determine the OID of memory usage:

snmpwalk -v 2c -c сommunity host .1.3.6.1.4.1.25506.2.6.1.1.1.1.8

Determine the OID of the temperature:

snmpwalk -v 2c -c сommunity host .1.3.6.1.4.1.25506.2.6.1.1.1.1.12

OID to view the ARP list:

.1.3.6.1.2.1.3.1.1

We look in what vlan are ip:

.1.3.6.1.2.1.2.2.1.2

See also:
SNMP OID and MIB for interfaces

When is it necessary to activate Long Range PtP Link Mode on airMAX?

In normal mode, airMAX sends a confirmation frame (ACK) after receiving the data frame, but at longer distances, it is better to disable this mechanism by setting the Long Range PtP Link Mode checkbox in the settings.

Depending on the channel width, the distance at which you want to turn on the Long Range PtP Link Mode can be different.

40MHz: 16.5 miles (26.5 km)
20MHz: 35.6 miles (57.3 km)
10MHz: 72.3 miles (116 km)
5MHz: 144.7 miles (232.9 km)

Note: this information does not apply to airOS 7, there is another timeout ACK algorithm.