Author: Yazeed

A friend of mine had a problem with a MacBook Pro, the problem was that it would not turn on, so i took a look at it and here is what i came up with

The battery was completely dead, effectively disabling the SMC (System Management Controller).

Without the SMC, the system will refuse to boot unless you bypass the SMC.

To bypass the SMS and make the computer run, you do the following

1- Disconnect the power cable.

2- Hold down the power button for 10 seconds (or more), then while still holding the power button down, connect the power cable and keep the power button pressed down for another 10 seconds (or more), then once the 20 seconds are over (10 without cable and 10 with cable), release the button and press it again like you normally would to start the computer.

Your fans will run at full speed (resulting in a loud computer), it will be slow, and it might crash or restart itself, in short things will not be working fine, what you need is a new battery.

------------------------------------------------------------
Stuff that only applies to my friend, so skip this part
------------------------------------------------------------
Here are the specs of my friends laptop.



When you want to look for a battery online, you should be looking for

Macbook Pro A1286 Early 2011 battery (Does not apply to all readers).

I did a search, but knowing that you will be taking it to a service person to install it means that a bad choice on my end (even with a money back guarantee) could mean paying twice to the repair person, so it is not as simple as it seems for me (Since you won't be installing it yourself).

The original battery (OEM) costs $110 it seems, batteries from other providers seem to cost anywhere from $25 to $70, with the $25 batteries having super bad reviews, and the ones for $70 being ok it seems. still, the complications (having to take it to someone to install it) leave me confused. so a safe bet would be the OEM (Original apple battery) but then that's more than double the price
------------------------------------------------------------

Once you install the new battery, you will need to reset the SMC, the repair shop will probably do the reset for you, but just in case.

Shut down the computer.
Plug in the power adapter.
On the built-in keyboard, press the Shift, Control, and Option keys on the left side and the power button, all at the same time.
Release all three keys at the same time.
Turn on the computer.

You are done

My tiny MP3 player has

The board : JHC-010.V5
The Chip : gp02101

The chip is nowhere to be found online in order to see what it can play other than MP3, the photos are on my phone, i will try to remember to post them here….

NOTE: this is not about battery operated 4G modems (such as the huwawei E5577 for example), see here for instructions to connect 4G modems via USB to openwrt

This is a 4MB space tp-link router, here are the steps

opkg install kmod-usb-serial kmod-usb2 luci-proto-3g kmod-usb-serial-option usb-modeswitch kmod-usb2 kmod-usb-serial-wwan kmod-usb-serial ppp comgt 

A package required for older releases of openwrt

opkg install sdparm

And the optional package

opkg install usbutils 

Now, reboot the router, then go to the routers LUCI interfaces page, then add an interface

From the drop down, chose UMTS/GPRS

On the next page, you should see one of the devices names /dev/ttyUSB0, in my case there are 2 since the device provides a storage controller, the modem was on USB0 not USB1, your might be different (try both if you have 2)

Now i chose UMTS only so that the modem will always use 3G because edge is good for nothing

Then your APN and username/password as you would on a phone or anywhere else… then save and apply

Since this router has around 600 to 700 KBs of free space, running the hi link USB dongle modem should be done with the bare minimum packages
Here are the ones i installed to get mine running

opkg install kmod-usb-net kmod-usb-net-rndis kmod-usb-net-cdc-ether udev usb-modeswitch kmod-usb-serial-option kmod-usb-net

Right after, i rebooted, then running the command,

ifconfig -a

I got a new eithernet device (USB0), on another older hi link dongle it was called eth2.

Then, from within LUCI, you can simply add a new interface using this hardware interface, and set that to DHCP and add it to the WAN segment, You are done, it should be connected now

Please be aware that once you have it running, you might want to get into the dongle’s interface settings, and instruct the dongle to only use 3G (Not GSM/EDGE), i do that by visiting 192.168.8.1 (Hard coded, can not be changed, but depending on the model yours might be different).

Well, we all know FTP, HTTP and other protocols would do the trick, but they are not the fastest way. because of setup and other considerations, especially when we are planing to use both windows and linux in the transactions, a low overhead method would be samba, or windows network file sharing

In windows, it is simple, we all know how to share a folder, and we all know how to open a shared folder over the network, in linux it is just as simple.

The detailed explanation of how to setup the samba server and share a folder is already in a post, but from the client side, you can copy a file by simply mounting the shared drive onto the linux server and copy or move files like you would a normal file or folder.

To mount we can simply execute the following

1- Install the client tools to mount the folder
apt-get install cifs-utils

then
mkdir /hds
mkdir /hds/smbmount

mount -t cifs //192.168.15.116/sharedfolder /hds/smbmount -o username=techg,noexec

That’s it, now use CP and MV as you would normally

One problem i faced with this method before was that my WD My Book Live shares would not mount, it threw an error

mount error(22): Invalid argument
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)

The logs did not provide much help either

CIFS VFS: cifs_mount failed w/return code = -22

Turns out that the WD MyBook Live has an older version of Debian, and samba on that device had a max-v of 2, so the solution is to connect while specifying which version of samba works

mount -t cifs //192.168.2.116/sharedfolder /hds/smbmount -o vers=2.0,username=techg,noexec

The values for Version can be 2.0 2.1 3.0

Mounting samba shares at boot time

My NAS server is always online, I switch my PC off while I am asleep, yes, being green may be a factor I claim, but the truth is, my personal machine has spinning hard drives, and my backups are not always up to date, so if a disk fails while I am asleep, and ticks it’s way to its own demise, I would then remember that I should have been more green, Anyway, let us get to the mounting

1- create the file /home/qworqs/.smbcredentials and fill it up with the contents below

username=qworqs 
password=qwarks
domain=

Now that we have our credentials stored somewhere, we can add the following line to our fstab file, yes, it makes no sense that I have a folder called /hds that I mount all my disks and network shares to, but I have been doing this since I was young

So, open the file /etc/fstab and add the following line

//192.168.1.100/sharename /hds/100share cifs credentials=/home/qworqs/.smbcredentials,rw,uid=qworqs,gid=qworqs,noauto,nofail,x-systemd.automount,_netdev      0       0

Google talk stopped working today, but i am so used to it, i don’t think i can live without it.

When i try to login, it says, username and password do not match, (You provided somename).

So here is the plan to make google talk work again.

PLEASE LEAVE A COMMENT IF YOU WOULD LIKE ME TO MAKE THIS SERVICE PUBLIC

The google talk installer is all over the internet, google talk uses XMPP as a protocol

I will be creating a server, and creating a file to make google talk connect to my server

Now i will tell all my friends to register their existing email address with this server and to run the file that changes the server for google talk, and we should be back online again

I will be monitoring my own instance of google talk for incoming and outgoing data so that i can modify the server so that it would become fully compatible since google talk is not 100% XMPP.

I will keep everyone posted on this. Hopefully i will have it working by the end of the day

Because i use lead acid batteries on my UPS systems, i will be putting all the relevant information that i need on lead acid batteries here

1- What does 74ah (74 amp per hour mean)
In most cases, it means 3.7ah over 20 hours, so you can draw 3.7 amps for 20 hours before the voltage drops to 10.5V, the equation is not linear, so basically you will be able to draw less than 7.4ah in 10 hours (Less than double for half the time), the rating is usually 20 hours on most batteries, the Bosch car batteries (S3 S4 S5…) are measured for 20 hours for example.

The CCA are usually measured for a 10 second period until the voltage drops to 7.5V (Yes, minimum of 7.5V not 10.5)

Now, sometimes, i connect an inverter and a power supply and a battery together, so that the inverter draws from the power supply, while the battery is technically maintaining its charge, if you can’t control the current, and just want the charge to stay put, something between 12.6 and 12.7 is a good voltage, but to be on the safe side, fully charge your battery, then let it sit for 24 hours, then get a voltage reading, tune your power supply to that voltage, and connect them all together.

After spending the day trying to figure out why firefox was not caching images from my website even though chrome seems to honor the caching headers from the server correctly, it turned out that my browser settings were not correct

Somehow, caching was disabled in firefox, to enable it i did the following

visit about:config (fill it into your address bar), this will give you your browser settings

in the top box, type in browser.cache

Make sure both browser.cache.memory.enable and browser.cache.disk.enable are set to true, if they are not, you simply double click it to flip it.

Close this window and try (no need to restart firefox).

To make a long story short, the most efficient way of doing this is simply to change the document root according to the sub domain

So within your server stanza, you can simply do the following

server_name ~^(?.+)\.tech-g\.com$;
    root /var/www_nginx/$sub;

This way, when you add a directory such as myothersite.com inside your nginx web directory, visitors comming to myothersite.com.tech-g.com will end up being served content from the directory /var/www_nginx/myothersite.com

No rewriting URLs needed, and no evil if statements either

Had problems with

apt-get install mysql-server

dbconfig-common: writing config to /etc/dbconfig-common/phpmyadmin.conf
Setting up mysql-server-5.5 (5.5.37-0ubuntu0.14.04.1) ...
/var/lib/dpkg/info/mysql-server-5.5.postinst: line 146: logger: command not found
ATTENTION: An error has occured. More info is in the syslog!
/var/lib/dpkg/info/mysql-server-5.5.postinst: line 236: logger: command not found
dpkg: error processing package mysql-server-5.5 (--configure):
subprocess installed post-installation script returned error exit status 127
dpkg: dependency problems prevent configuration of mysql-server:
mysql-server depends on mysql-server-5.5; however:
Package mysql-server-5.5 is not configured yet.

So the sollution was to remove mysql completely,

sudo apt-get purge mysql*
sudo apt-get autoremove
sudo apt-get autoclean

then run

apt-get dist-upgrade

then installing mysql-server again

apt-get install mysql-server