Ahsaniqbalkmc

oh.... Its such a bad news..... not only because I will have to spend extra to repair my printer now but also because my experiment with refilling the toner myself is likely to have caused it.... I would rather leave it like this for now.........

It might not be necessary. But I was assuming the scenario where a person would want to shift to the wifi directly after first boot. As I have also told to run the commands for updates: sudo apt-get updatesudo apt-get upgrade So it will be a good idea to power off the system and restart it. Normally a "reboot" command would be preferred but the reboot behavior doesn't fit well with access via SSH (at least I feel this way) so I decided to opt for "poweroff".

Thanks for making me understand what "ca-certificates" is. And also for providing an insight into what git might be. Following the source you provided, I searched for git and found that it's a "SCM tool" (Software Configuration Management tool). So after doing a little research, I developed an understanding of what a SCM is (and thus what git is) and I thought it would be good to share it here, So basically a Software Configuration Management tool is a tool that tracks and controls changes in the software. The thing becomes easier to understand when we see it parallel to the open source community. Open source software have usually a community of developers behind them. Anyone in this community can change the code and add things to it. So there must be some means of tracking and controlling these changes and people who make them. This is the job of a SCM (git in this case). It tracks what changes are made, when they are made, and who has made them. It also controls who can make changes to the software. The outcome of the software after the changes is noted and tracked and if they have a negative impact, the changes can be reversed. So git (and other SCMs) make sure that open source software isn't subject to non-useful and harmful code modification. It also makes easy to track the changes made in different versions. Overall it makes open-source software more reliable. Additions (or modifications) to my understanding of git and other SCMs is welcome.

Using WIFI instead of the Ethernet Cable for Headless PI: After successfully booting up Raspberry pi without a monitor, its time to move forward and make my pi more mobile and easily accessible. The first step to achieve this is to get rid of the ethernet cable, which limits the pi to be placed near the router only as far as the length of the ethernet cable. I want to get rid of this limitation so that I can keep my pi near me (instead of the router). And for this, the first thing that comes to mind is "establishing connection with the router via wifi instead of the ethernet". A USB WIFI adapter is needed: Now the pi doesn't have built in wifi module. So you have to buy an extra device called "USB WIFI Adapter" or "USB WIFI Dongle". Luckily for me, I had one laying around so the process became easier and natural for me. The device I have is TP-Link TL-WN727N. It is considerably cheap. I bought it for PKR 900 (about $9) some time ago. Below is the picture of the device with its packaging: Luckily for me, the USB WIFI adapter worked with pi out of the box. I.e. it didn't have to install any drivers and face other mess. So if you are not familiar with installing drivers and stuff on linux (which for newbies is significantly harder than installing drivers on windows), then make sure that the wifi adapter you buy works with pi out of the box. Basic Principle: The principle behind this is simple. Previously we used an ethernet cable to connect the pi to the router and then obtain access via SSH. And through SSH do things on pi like set up VNC server and other things. And then via VNC server operate the pi like a normal scenario (i.e. pi with monitor attached to it). Here we will just change the means of connecting pi to the router from ethernet to wifi. Thus the pi would be connected to the router without any cables and therefore the limitation of placing the pi at one place is omitted. I should clarify one thing here. Prior access to pi is needed before we can set up the wifi connection. So you cannot make a FIRST HEADLESS BOOT with wifi. You still need to connect using ethernet (or use a monitor) to set up wifi and then when all is set, you can say good bye to the ethernet (or monitor). Procedure: Follow the procedure in the first post so that you are able to interact with the pi and perform necessary setup for wifi. Make sure you follow all the steps till the last (18th). Once it is confirmed that you are able to view the raspberry pi desktop and interact with it, open a terminal window and enter the following command to turn your pi off sudo poweroff Once the pi has powered off. Insert the usb wifi adapter into a usb port. Leave the ethernet cable inserted as before. Start the pi by unplugging the power supply and plugging it again. Once the pi has restarted, start putty on your windows machine and connect via SSH to the pi by following method described in first post. Also start a vncserver on the pi by method described in the first post. Start vncviewer and connect to the vncserver of pi (as described in the first post). Once you are able to see the desktop, start the "wifi config" tool on the desktop. Click the scan button. This would open the scan results dialogue box. Click the scan button on dialogue box. The pi will start scanning for your wifi network. Once it has been found, double click on it. A new dialogue box would open. Here insert the password (in the PSK field) and click add You should now be connected to your wifi and should see something similar to the image below: You can also see your IP address here. From now on you can unplug the Ethernet cable permenantly and use the ip address of your wifi connection for both SSH and VNCserver. NOTE: The IP addresses in these tutorials are automatically assigned by the DHCP server. These can change overtime so it is a good idea to confirm the ip address of your device by checking the DHCP client list (as described in the first post step no. 5). If your router supports it, you can reserve specific IP addresses for your device so that it would always be given the specified IP address. For this you need to check your routers manual. It is also possible to make the PI use fixed IP address. But as of now, I don't know how to do this.

oh... Forgot to add the picture of the Raspberry PI desktop

It really is a great device. I had to pay about double the original amount but I think its worth it. I have had it for about 3 days now and I have learned quite a lot of useful stuff. I wish you luck in your quest of finding the PI....

Maybe I didn't make myself clear when I said this: What I wanted to say was that I understand that this command is going to install ca-certificates. However I don't know what is "ca-certificates". So I am interested in knowing What is "ca-certificates" ? What does it do ? Why is it important to install before running rpi-update ? I think I have made myself very clear now. Same goes for the second command. I understand that it would install git-core but I don't know what is "git-core". So I am interested in knowing: What is "git-core" ? What does it do ? Why is it important to install before running rpi-update? About the third question I asked, I need you to confirm that I have understood your explanation correctly. My understandig of the wget -O is: "wget is the command that enables you to download stuff via the command line. It has many options including -O. This -O option enables you to store the downloaded info in a specified way i.e. you can describe the file name and directory in which the downloaded stuff would be stored. So when using -O option, you need provide the directory and filename. Furthermore -O also makes sure that the downloaded stuff is run automatically after the download is complete" Please confirm that my understanding of the wget and -O is correct.

Raspberry pi is a wonderful piece of hardware. The possibilities of doing all kinds of stuff with it are enormous. Moreover, it has a very active online community and people are trying to do all kinds of things with it and sharing it with the world. So if you are having any issues with the raspberry pi, you are most likely to find solutions online. My problem: The issue I had was absence of a display device for the raspberry pi. As you might know, the pi supports only hdmi and composite video interface. The HDMI is common in new monitors and HD TVs while the composite video (RCA) is common in older tvs and smaller displays. My problem was that I have a spare monitor which only has VGA interface and there is no VGA interface in the raspberry pi. So in order to connect this monitor to the pi, I needed a small device called “HDMI to VGA adapter”. A simple cable won’t do because HDMI and VGA are two different kinds of signals and need to be converted by proper electronic components. However, the price of the adapter is an issue. I tried to find it in a local store and I was told that it would cost me PKR 4500 (about $45). This is way too much when I can spend the same amount of money and exchange my current monitor with one that has built in HDMI support. But presently, I don’t intend to spend money getting a new monitor. So the only option I was left with was booting my raspberry pi headless (i.e. without a monitor). I did some quick research on Google and found without spending much time that it is possible and not very difficult (thanks to the active raspberry pi community) Raspberry pi first boot in normal scenario: For a raspberry pi to function in a normal scenario, the following components are needed: Power supply (most smartphone chargers would work fine) SD card (more than 4 GB is recommended and 2GB is the least requirement) Monitor (not absolutely necessary but we are talking about normal scenario here) An input device (such as a keyboard) It should be noted that raspberry pi has no storage of its own. It depends on the SD card to store the OS that would make the raspberry pi to work. So in order to boot the raspberry pi in a normal scenario, first of all you need to place the raspberry pi OS onto the SD card, and this would require another computer (not a problem nowadays). Before this it is recommended to format the SD card using the “SD Association’s Formatting Tool” Placing a raspberry pi OS on the SD card can mean simple copying of the contents of the NOOBS.zip file (NOOBS = New Out Of The Box Software) onto the SD card or it can mean writing on OS image (such as Raspbian Wheezy OS) on the SD card with the help of special tools like Win32DiskImager. When you have successfully placed the OS on the SD card, all you need to do is insert the SD card properly into the pi, plug in the power supply and connect the monitor. That’s it. The remaining setup is easy and you just have to follow the instructions appearing on the screen. Principle of headless booting: Headless booting (i.e. booting without a display device) is a bit different that normal booting. In this scenario you don’t have monitor or any other display device. And since you don’t have monitor the use of keyboard becomes pointless as well. But you need some means of connecting to the raspberry pi and talking to it. And this is where SSH (Secure Shell) comes to the rescue. SSH is a network protocol that among other things, enables you to use the command line remotely. For SSH to work, you need a network connection to the pi which can be obtained by connecting the pi to the router using an Ethernet cable. Then using SSH, you can easily install VNC server for a graphical connection to pi where you can actually see the desktop of your pi as you would see on a directly attached monitor. So using SSH and VNC, you can operate the raspberry pi via your laptop or home PC. So for headless booting, three things are required: Power supply (same as above) SD card Network Connection (preferably via Ethernet cable to the router) It should be noted here that the NOOBS package won’t work with headless first boot because it requires you to perform a few actions before actual OS is installed onto the SD card. And it is not possible to perform these actions without monitor and keyboard attached. So in this scenario, the NOOBS package is not going to work. Instead you would need to write the image of an OS (Preferably Raspbian Wheezy) to the SD card using Win32DiskImager (if you are on windows) or dd tool (if you are on linux). Procedure for headless first boot: First of all, make sure that you have all the required components ready and in working condition. The components required for headless first boot are: Raspberry pi itself Power Supply SD card Network connection Format the SD card using the SD Associations Formatting Tool (link above). Download the latest Raspbian OS image.and write it to the SD card using Win32DiskImager (in windows) and dd tool (in linux) Plug in the SD card into the raspberry pi, insert the Ethernet cable and connect the power supply. You would see the lights of the raspberry pi turn on. Wait for a minute or two so that the pi can boot up completely. To connect to the pi via SSH, you first need to know the IP address of the pi. For this, you can login to the admin section of your router and check the DHCP client list. If you are on windows, you would also need a SSH client (because there is not built in one). Putty is a good SSH client, and is also free so I recommend it. If you are on a linux machine, you don’t need to install anything new. Windows users: After installing putty, open it, you would see a window like the image below. You need to enter the IP address of the PI and click connect (I have entered the IP address of mine). After the connection is established, you would be presented with a window similar to the following: Enter the username “pi” (without quotes) and password “raspberry” (without quotes). And you SSH connection with the pi would be established. That’s it, you are now connected to the pi. It is a good idea to run the config utility, because its your first boot and you may need to set certain things up. To run config utility, enter the following command: Sudo raspi-config After the configuration is complete, it is a good idea to update your raspberry pi. You can easily do it by running the commands: Sudo apt-get updateSudo apt-get upgrade After that, if you wish to install the VNC server, so that you can operate the pi in a graphical way, run the following command: Sudo apt-get install tightvncserver After tightvncserver is installed, run the following command to start the vncserver on the pi: Sudo vncserver :1 –geometry 1024x768 (or any other desired window size) –depth 16 (or any other colour depth) After running this command, you would be asked for a password for the vncserver. Use your desired password. You would also be asked if you like to use a password for read-only mode. Provide one if you want to use read-only mode. To interact with the vncserver on the pi, you need to install a vnc client on your windows machine. For this, install Ultravnc on your windows machine. Once ultravnc is installed, open the ultraVNCviewer, enter the IP address of the pi followed by “:1” (without quotes) and click on connect button. You would be asked for a password. Provide the password you used when setting the vncserve on the pi. If you want to enter the read-only mode, provide the password you set for read-only mode. And that’s it. You would see a screen showing you the desktop of the pi. From here, you can use pi like you would use it in a normal scenario,

While playing with my pi, the first thing i did was update the packages, using commands: sudo apt-get updatesudo apt-get upgrade However, while looking for stuff online, I came across a tool to update the raspberry pi firmware. Now I don't REALLY understand what is meant by updating the raspberry pi firmware ( something like updating BIOS of PCs ?? or Something like updating kernels of linux machines ?? Or something else) but because its an UPDATE, I decided to do it. The tool is rpi-update developed by Hexxeh. So I went on and ran the following command on my raspberry pi: sudo apt-get install rpi-update But I was told that the package is already installed. Then I ran sudo rpi-update And nothing really happened. So I decided to find some help online. I found an aritcle which had commands as shown below: sudo apt-get install ca-certificatessudo apt-get install git-coresudo wget http://goo.gl/1BOfJ -O /usr/bin/rpi-update && sudo chmod +x /usr/bin/rpi-updatesudo rpi-updatesudo shutdown -r now And here comes the problem of not understanding what I am doing. So I am on this forum to ask for help: ??? The first command installs ca-certificates, but I don't understand what are ca-certificates and what they do ??? Same situation with the second command i.e. what is git-core and what does it do ??? The third command is the main problem and that why I decided to give thic topic a relative title. The problem here is that I understand that the command is telling the pi to download file from https://raw.githubusercontent.com/Hexxeh/rpi-update/master/rpi-update however I don't understand the second part of the command. I searched online for help and found this: I really really don't understand this. Any help would be appreciated:

As I have repeatedly mentioned, I am a medical student but i have huge enthusiasm for computers and stuff. As a result, I spend more time on my computer than doing what I am expected to do.... As a result of this enthusiasm, I occasionaly try to get my hands on the new stuff. Raspberry pi is not quite "NEW" but it is difficult to obtain, especially in areas where there aren't many official distributors. I had a wish to get it as soon as possible after the release of 512mb version but I didn't have the means to pay for it. Luckily, I found out that a store in another city has a few of these devices in stock. They have an online ordering faciltiy (online store) where I ordered the device. The price was an issue because they were demanding more than twice the actual price of the device, but as I had no other options, I decided to pay the extra money. So after two days of ordering, I received my device via a local courier service: The packaging was minimal (as is all over the world). Inside the envelope, there was an invoice and the Raspberry pi in its own very minimal packagin: As it can be clearly seen in the invoice, the amount I paid for the pi was PKR 6600... This is about $66 which is about double the price set by the original distributors. But when choices are limited, you have to pay extra.. So the box containing the raspberry pi clearly stated element14.com on it. I think they are one of the official distributors of the device and realted to Farnell.. But i don't care because I had no chance of buying directly from them. The box looks like this: Front: Back: So the packaging is very minimal (as is the raspberry pi itself). Inside, there was the raspberry pi itself and an instructions leaflet. See images below: So this is my new raspberry pi. When I decided it, I didn't have many uses for it in mind. I just wanted to have a feel of it and play with it a bit. I am not an expert linux user by any extension of the thought. In fact, I am not even an average linux user. I have made a few attepmts previously to try to master the linux beast but I had to give up for one reason or the other. However, because of my previous attempts, I can do the very basic stuff by myself and I am quite sure that this would help me playing with the pi. After getting the pi, the first thing I intend to do is to get my hands dirty with the linux OS. Try to master it and do things that I can do with my windows machine easily. I also spent some time seeing what other people are doing with their pi(s) (thanx google and internet). And now I can thing of a few pretty useful things i can do with it. First would be a testing server to sharpen my web development skills. I am sure that this would make me understand networking and connecting to servers in a better way. Another use I can thing of is a dedicated 24/7 torrenting client. there are many other ideas, but the most important thing for me is that it would enable me to learn new stuff in a better way.....

There is an update to the situation. Yesterday when I had to print about 50 pages I noticed something that I thing can help in diagnosis of the issue so I am sharing it here. So when I printed the 50 pages, the last pages of them had these lines lightened out. I mean to say that these unwanted lines were very light in these pages. See image below: As it can be seen in the image, the unwanted lines are very light and not so bothering (but they are still there I would love to get rid of them). However, to confuse the situation further, after printing these 50 odd pages, I gave the printer some rest (about 30 minutes) and then I printed another page. To my frustration, the page again had the similar unwanted lines as the image in the first post of this topic i.e. the unwanted lines were again quite dark and very annoying. So in summary, the lines become light when I do a lot of printing but when I just start printing, the first few pages have again these lines quite dark. Anyone ?????

I have a samsung printer (Samsung Ml-1675) that I have used for quite a while now. I have been quite happy with it and it got the job done brilliantly until there was no more toner in it. Then I faced a problem (as discussed here; http://forums.xisto.com/topic/56929-flashed-custom-firmware-to-my-printer-is-it-legal/ '>Flashed custom firmware to my printer). In short, to avoid recurrent heavy maintenance charges, I flashed a custom firmware which makes me able to just put the toner in myself and continue the printing process without spending anything extra on buying counter chips and stuff... But since I have done the DIY repairing process, the printer started to print unwanted horizontal lines on every print. Below is the picture of the lines: As can be seen in the image, the page has horizontal lines at regular intervals. And this happens with every page I print, no matter whether empty or full... A strange thing that might be helpful with the diagnosis is that when I print a completely black page, the horizontal lines appear to be less dark than the rest of the page. I googled a few terms in hope of finding some solution. But unfortunately couldn't find anything valuable about the issue. I also tried cleaning the drum. When I opened it, there were black lines on the drum, which were easily removed by cloth. However, the first print after the cleaning process again contained those horizontal lines. After performing some more printing, I opened the drum again and there were again similar black lines on it. So something is causing the toner to stick to the drum in that specific are in that specific fashion. I also tried to clean the rest of the printer both with cloth and an air blower, but this was of no use. So any sugestions on what is causing these recurrent black horizontal lines and more importantly how to get rid of them would be hightly appreciated.

WOW,,, That's some explanation @yordan... Hats off to you.. You have made me change my mind. Now I think that I should stick to what I have and not spend money until I really really need to... For instance, I would think about buying an SSD only if my current HDD fails and I absolutely have to buy a storage device.

Is the performance worth the price? I mean how much difference it is going to make if I just replace the hard drive of my current laptop with an SSD. I have read in many places that SSDs are significantly faster and considerably reduce the loading times of various software. How much truth there is in this....???

hmmm... So its better to stick with technology that is meant for personal use and that is in a price range suitable for personal use...

oh.. Its too expensive for me. But are these adapters absolutely necessary for every pc. I mean aren't there any motherboards that provide SAS connectivity without the need of such adapters. I am guessing that these boards would be expensive too but they should have other great features as well...

Actually you did a wonderful job. You made me realize that the minimal knowledge I have about servers is so incomplete that it makes my perception faulty. I didn't really know that the word "server" is used in so many related but quite different ways. I think I need to improve my background knowledge significantly.

Great explanation @yordan... My next question would be: Suppose I want to use a SAS disk on my current laptop, which doesn't appear to have the "whatever" that is required by a SAS disk. So is this possible that I add this "whatever" to my laptop so that computer becomes compatible with SAS disks. Or this is some kind of built in feature, which would employ that I would have to buy a new mother board (or possibly a new computer) that is made compatible with the SAS disks during manufacture. I hope you get what I mean..... :/

So you intall apache 2 virtual host on a computer (probably a server) that is intended to host websites. I don't know much about the mechanics of hosting but from what I know the ideal scenario is that a computer (server) has an operating system designed for its use as a server. That operating system provides tools to run a website. Now according to my knoweldge, if you want to host multiple websites on a single machine, you would have to create virtual machines, each hosting a single website. So in this way many websites can be hosted on a single machine, giving rise to the term shared hosting. But this apache 2 virtual host is something really new for me. Is it some kind of alternative to what virtual machines do. Or there is some basic fault in my understanding. in either case, I would love to know the answer.....

Yeah I can chill now cuz the problem is solved. Thankfully you didn't tell me to chill when I was stuck hopelessly....

So what you are saying @yordan is that you can't use SAS drives on normal laptops or desktops.... Is this right ???

It might sound stupid, but what is Apache 2 virtual host. What is it used for ???

@opaque I think it would take a whole website if they just wanted to clear out the generic and multi-meaning talk of matt cutts,..

... Adaptation...

What about the Bezel portion of the screens in between. I am definitely sure it would ba annoying but how much ???