Akhir Cerita Doraemon


There are three current and often quoted urban legends that started spreading in late 1980s of an ending to the Doraemon series.

* The first and the more optimistic ending was made public by Nobuo Sato several years ago. Doraemon’s battery power ran out, and Nobita was given a choice between replacing the battery inside a frozen Doraemon, which would cause it to reset and lose all memory, or await a competent robotics technician who would be able to resurrect the cat-robot one day. Nobita swore that very day to work hard in school, graduate with honours, and become that robotics technician. He successfully resurrected Doraemon in the future as a robotics professor, became successful as an AI developer, and thus lived happily ever after, thus relieving his progeny of the financial burdens that caused Doraemon to be sent to his space-time in the first place. A dojin manga for this ending was made by a “Tajima T Yasue” in 2005, and it sold 13,000 copies before Shogakukan halted its publication. Tajima apologized to Shogakukan in 2007 and paid an undisclosed amount of money for settlement.[6]. See reference for scans of the ending.[7]

* The second, more pessimistic ending suggests that Nobita Nobi is suffering from autism and that all the characters (including Doraemon) are simply his delusion. The idea that Nobita was a sick and dying little boy who imagined the entire series on his sickbed to help him ease his pain and depression no doubt angered quite a lot of fans. Many Japanese fans staged a protest outside the headquarters of the publisher of the series after learning about this suggestion. The publisher had to issue a public statement that this is not true. (This ending actually correlates to the ending for the series St. Elsewhere, which ended in 1988.)

* The third ending suggests that Nobita fell and hit his head on a rock. He fell into a deep coma, and eventually into a semi-vegetative state. To raise money for an operation to save Nobita, Doraemon sold all the tools and devices in his four-dimensional pocket. However, the operation failed. Doraemon sold all his tools except for one used as a last resort. He used it to enable Nobita to go wherever he wanted, whichever time or era he wished to go. In the end, the very place Nobita wanted to go was heaven.

The plausibility of these issues was discussed here and it was concluded that there is no ending to Doraemon. [8]

There are three official endings to Doraemon that were made. Doraemon was discontinued in two media because readers were advancing in grades and an ending was believed to be needed. These two are not reprinted.

* In the March 1971 issue of the magazine Shogaku 4-nensei [9]: Due to the fact that visitors from the future were causing too much trouble, the government in the 22nd Century passed a bill to ban time-travelling altogether, meaning Doraemon would have to return to his time era. He leaves Nobita.

* In the March 1972 issue of the magazine Shogaku 4-nensei: Doraemon, for some reason, had to go back to the future but fakes a mechanical problem so that Nobita would let him go. Nobita believes him and promises to wait until Doraemon gets well. Realizing that Nobita can handle his departure, Doraemon tells the truth and Nobita accepts. Doraemon returns to the future.

The third ending was actually meant to be the official ending due to low TV ratings and the Fujiko Fujio duo was busy with other works. But Doraemon did not leave their minds and restarted from next month’s issue. In 1981, this episode was made into anime (called “Doraemon Comes Back”), and in 1998, this was released as an anime movie.

* In the March 1973 issue of the magazine Shogaku 4-nensei, Nobita again returns home after losing a fight against Gian. Doraemon then explains that he has to return. Nobita tries to have Doraemon stay but after talking it over with his parents, he accepts Doraemon’s departure. They take a last walk in the park. After they split up, Nobita encounters Jaian and gets into a fight again. After a long duel with Nobita trying to win at all costs so that Doraemon can leave without worries, Gian lets Nobita win for not giving up. Doraemon finds Nobita passed out and takes him home. Sitting beside sleeping Nobita and after a moment of thought, Doraemon returns to the future. (It is also found at the last chapter of the manga Book 6).

* The animated version is completely similar but lengthened. Nobita finds a box the shape of Doraemon in his drawer. The next day, which happens to be April Fool’s day, Nobita is jeered at by Suneo and Jaian, the latter tricking him about Doraemon’s return. He happily runs home and asked his mother whether Doraemon came back and finds out the truth. Nobita couldn’t stand it and opens the box. Inside of it was a bottle of liquid. He hears Doraemon’s voice explaining that the potion is called Uso 800 (Lies 800) it is used to make all untruths the drinker says true. Nobita uses it to play a few tricks on Jaian and Suneo, like first taking cover then say that the weather sure is good, which becomes a lie and it started to rain heavily before he said it is raining heavily and the rain stopped. Jian and Suneo was scared away after a few tricks and when Nobita mentioned what is happening. Nobita was very happy at first but quickly loses interest in the absence of Doraemon. As he walks home, due to his earlier questioning if Doraemon returned or not, his mother asked him if he could find Doraemon, he unwittingly said, in great disappointment, the truth about Doraemon never coming back, just like what Doraemon told Nobita before his departure. Since the potion was still in effect, when he arrives his room he finds Doraemon there, and they have a happy reunion, but due to the effects of the potion, all his greets and joyful words have to be spoken in the opposite way like I am so unhappy that we can never be together again.. The extended ending from the animated series was eventually adapted to the first story of Book 7 in the manga series, with a few changes (i.e. Instead of hearing Doraemon’s voice explaining the use of the potion, he finds a card inside the box describing the use of the potion).

When the Fujiko Fujio duo broke up in 1987, the very idea of an official ending to the series was never discussed. Since Fujiko F. died in 1996 before any decisions were reached, any “endings” of Doraemon are fan fiction. However, it is apparent from many episodes and movies where Nobita travels to the future that in the end he does marry Shizuka, leads a happy life and separates with Doraemon, although Nobita and his friends fondly remember him.

Hope you like it

Sumber : kaskus.us

Block download based on file SIZE …

I forgot the guy’s name who is from FB, who asked me a question, lets name him Mr. X. The query was > howto block downloads of large files (lets say 5mb or above ) in specific timings (like 8pm-12am).

But the issue is How the router will know the file size before it’s downloaded? The router has no way of knowing how big a connection is… An workaround is to create a Firewall Filter rule that will will allow the first 5MB of a connection through, and once it reaches that, it will start to drop packets. I used it a network in Gulistan-e-Jauhar, and it worked good.
But do remember that that It will also affect streaming, RDP like protocols, VPNs, and any other connection that transfers a large number of bytes.

/ip firewall filter
add action=drop chain=forward comment="downloading of files larger then 5mb (It will break connection after 5mb of transfer) applicable from 8pm till 12am / zaib" connection-bytes=5242880-0 disabled=no protocol=tcp time=\


source : https://aacable.wordpress.com/tag/lock-download-based-on-file-size/

Mikrotik How to block Winbox Discovery + Limit Winbox Access

To hide your mikrotik from being appearing in WINBOX scan negibour list, & to limit WINBOX access from your admin PC only,
Use the Following.

/tool mac-server
add disabled=yes interface=all
/tool mac-server ping
set enabled=no
/ip firewall filter
add action=drop chain=input comment="block mikrotik discovery" disabled=no dst-port=5678 protocol=udp
add action=drop chain=input comment="ALL WINBOX REQUEST By MAC Address" disabled=no dst-port=20561 protocol=udp
add action=drop chain=input comment="ALL WINBOX REQUEST EXCEPT FROM MY PC" disabled=no dst-port=8291 protocol=tcp src-address=!

You can Also Disable Network Neighbor Discovery on the interface to which your network users are connected

Example: /ip neighbor discovery set ether1 discover=no

source : https://aacable.wordpress.com/tag/lock-download-based-on-file-size/


/ip firewall mangle
add action=add-src-to-address-list address-list=Worm-Infected-p445 address-list-timeout=1h chain=prerouting connection-state=new disabled=no dst-port=445 limit=5,10 protocol=tcp
/ip firewall filter
add action=drop chain=forward disabled=no dst-port=445 protocol=tcp src-address-list=Worm-Infected-p445
add action=drop chain=forward disabled=no dst-port=445 protocol=tcp src-address-list=Worm-Infected-p445
source : https://aacable.wordpress.com/tag/lock-download-based-on-file-size/


A basic Mikrotik Firewall Script to secure MT box from virus and flooding. First copy all contents of below script to notepad, then carefully read it.

/ip firewall filter
# To Block ICMP on your WAN Interface
add action=drop chain=input comment="Block ICMP on WAN interface" in-interface=pppoe-out1 protocol=icmp
# Add flooding ips coming from the internet to the Blocked List for 1 mnt
add action=jump chain=forward connection-state=new jump-target=block-ddos
add action=drop chain=forward connection-state=new dst-address-list=ddosed src-address-list=ddoser
add action=return chain=block-ddos dst-limit=50,50,src-and-dst-addresses/10s
add action=add-dst-to-address-list address-list=ddosed address-list-timeout=1m chain=block-ddos
add action=add-src-to-address-list address-list=ddoser address-list-timeout=1m chain=block-ddos
add action=drop chain=input comment="BLOCK DNS REQUEST ON WAN INTERFACE" dst-port=53 in-interface=pppoe-out1 protocol=udp
# Block PORT Scanner Users for 2 minutes
add action=drop chain=input comment="ping port scanners" src-address-list="port scanners"
add action=add-src-to-address-list address-list="port scanners" address-list-timeout=2m chain=input comment="Port scanners to list " protocol=tcp psd=21,3s,3,1
add action=add-src-to-address-list address-list="port scanners" address-list-timeout=2m chain=input comment="NMAP FIN Stealth scan" protocol=tcp tcp-flags=fin,!syn,!rst,!psh,!ack,!urg
add action=add-src-to-address-list address-list="port scanners" address-list-timeout=2m chain=input comment="SYN/FIN scan" protocol=tcp tcp-flags=fin,syn
add action=add-src-to-address-list address-list="port scanners" address-list-timeout=2m chain=input comment="SYN/RST scan" protocol=tcp tcp-flags=syn,rst
add action=add-src-to-address-list address-list="port scanners" address-list-timeout=2m chain=input comment="FIN/PSH/URG scan" protocol=tcp tcp-flags=fin,psh,urg,!syn,!rst,!ack
add action=add-src-to-address-list address-list="port scanners" address-list-timeout=30m chain=input comment="ALL/ALL scan" protocol=tcp tcp-flags=fin,syn,rst,psh,ack,urg
add action=add-src-to-address-list address-list="port scanners" address-list-timeout=2m chain=input comment="NMAP NULL scan" protocol=tcp tcp-flags=!fin,!syn,!rst,!psh,!ack,!urg
# Block Common Virus Ports
add action=drop chain=virus comment="Blaster Worm" dst-port=135-139 protocol=tcp
add action=drop chain=virus comment="Blaster Worm" dst-port=445 protocol=tcp
add action=drop chain=virus comment="Messenger Worm" dst-port=135-139 protocol=udp
add action=drop chain=virus comment="Blaster Worm" dst-port=445 protocol=udp
add action=drop chain=virus comment=________ dst-port=593 protocol=tcp
add action=drop chain=virus comment=________ dst-port=1024-1030 protocol=tcp
add action=drop chain=virus comment=MyDoom dst-port=1080 protocol=tcp
add action=drop chain=virus comment=________ dst-port=1214 protocol=tcp
add action=drop chain=virus comment="ndm requester" dst-port=1363 protocol=tcp
add action=drop chain=virus comment="ndm server" dst-port=1364 protocol=tcp
add action=drop chain=virus comment="screen cast" dst-port=1368 protocol=tcp
add action=drop chain=virus comment=hromgrafx dst-port=1373 protocol=tcp
add action=drop chain=virus comment=cichlid dst-port=1377 protocol=tcp
add action=drop chain=virus comment="Bagle Virus" dst-port=2745 protocol=tcp
add action=drop chain=virus comment=Dumaru.Y dst-port=2283 protocol=tcp
add action=drop chain=virus comment=Beagle dst-port=2535 protocol=tcp
add action=drop chain=virus comment=Beagle.C-K dst-port=2745 protocol=tcp
add action=drop chain=virus comment=MyDoom dst-port=3127-3128 protocol=tcp
add action=drop chain=virus comment="Backdoor OptixPro" dst-port=3410 protocol=tcp
add action=drop chain=virus comment=Sasser dst-port=5554 protocol=tcp
add action=drop chain=virus comment=Beagle.B dst-port=8866 protocol=tcp
add action=drop chain=virus comment=Dabber.A-B dst-port=9898 protocol=tcp
add action=drop chain=virus comment=Dumaru.Y dst-port=10000 protocol=tcp
add action=drop chain=virus comment=MyDoom.B dst-port=10080 protocol=tcp
add action=drop chain=virus comment=NetBus dst-port=12345 protocol=tcp
add action=drop chain=virus comment=Kuang2 dst-port=17300 protocol=tcp
add action=drop chain=virus comment=SubSeven dst-port=27374 protocol=tcp
add action=drop chain=virus comment="PhatBot, Agobot, Gaobot" dst-port=65506 protocol=tcp
add action=jump chain=forward comment="jump to the virus chain" jump-target=virus
add chain=input comment="Accept established connections" connection-state=established
add chain=input comment="Accept related connections" connection-state=related
add action=drop chain=input comment="invalid connections" connection-state=invalid
add chain=input comment=UDP protocol=udp
add action=drop chain=forward comment="invalid connections" connection-state=invalid
# Script Ends Here

Everything You Need to Know About SLC, MLC, & TLC NAND Flash

The Anatomy of an SSD

MyDigitalSSD BP4e mSATA SSD 

MyDigitalSSD BP4e mSATA SSD with two enclosed NAND flash memory chips installed. The controller chip is designed by PHISON

  • A. NAND Flash: The part where your data is stored, in blocks of non-volatile (does not require power to maintain data) memory.
  • B. DDR Memory: Small amount of volatile memory (requires power to maintain data) used to cache information for future access. Not available on all SSDs.
  • C. Controller: Acts as the main connector between the NAND flash and your computer. The controller also contains the firmware that helps manage your SSD.

What is NAND Flash?

NAND flash memory is built up of many cells that holds bits, and those bits are either turned on or off through an electric charge. How those on/off cells are organized represents the data stored on the SSD. The number of bits in those cells also determine the naming of the flash, for example Single Level Cell (SLC) flash contains a single bit in each cell.

The reason behind SLC only being available at lower capacities is down to the physical real estate the NAND flash occupies on the Printed Circuit Board (PCB). Don’t forget that the circuit board has to have the controller, DDR memory, and flash built to standard dimensions to fit inside your computer. MLC doubles the amount of bits per cell, whereas TLC triples, and this opens up for higher capacity SSDs.

There are particular reasons why manufactures build flash memory with a single bit per cell like SLC. SLC has the advantage of being the fastest, most durable but has the cons of being more expensive, and is not available in higher gigabyte storage capacity. That is why SLC is preferred for heavy enterprise usage.

MLC and TLC flash in comparison to SLC, is cheaper to produce, available in higher storage capacities, but at the tradeoff of relatively shorter life spans and slower read/write speeds. MLC and TLC are preferred for everyday consumer computer usage.

Understanding your own needs for computing and NAND flash basics will not only help you pick the right SSD, but will also help you figure out factors such as the price behind the product.

SLC (Single Level Cell)

The Single Level Cell flash is so called for it’s single bit that can either be on or off when charged. This type of flash has the advantage of being the most accurate when reading and writing data, and also has the benefit of lasting the longest data read and write cycles. Program read/write life cycle is expected to be between 90,000 and 100,000. This type of flash has done exceptionally well in the enterprise market because of it’s life span, accuracy and overall performance. You won’t see too many home computers with this type of NAND due to its high cost and low storage capacities.


  • Has the longest lifespan and charge cycles over any other type of flash.
  • More reliable smaller room for read/write error.
  • Can operate in a broader temperature range.


  • The most expensive type of NAND flash on the market.
  • Often only available in smaller capacities.

Recommended for:

  • Industrial use and workloads that require heavy read/write cycles such as servers.

eMLC (Enterprise Multi Level Cell)

eMLC is MLC flash, but optimized for the enterprise sector and has better performance and lastability. Read/write data life cycles are expected between 20,000 and 30,000. eMLC provides a lower cost alternative to SLC, yet maintains some of the pros of SLC.


  • Cheaper alternative than SLC for an enterprise SSD.
  • Has better performance and endurance over standard MLC.


  • Does not match SLC NAND flash SSDs in performance.

Recommended for:

  • Industrial use and workloads that require heavy read/write cycles such as servers.

MLC (Multi Level Cell)

MLC flash as it’s name suggests stores multi bits of data on one cell. The big advantage of this is the lower cost of manufacturing versus manufacturing SLC flash. The lower cost in flash production is generally passed onto you as the consumer, and for that reason is very popular among many brands. MLC flash is preferred for consumer SSDs for it’s lower costs but the data read/write life is less in comparison to SLC at around 10,000 per cell.


  • Lower production costs are passed onto you the consumer.
  • Is more reliable than TLC flash.


  • Not as durable and reliable as SLC or enterprise SSDs.

Recommended for:

  • Everyday consumer use, gamers, and enthusiasts.

TLC (Triple Level Cell)

Storing 3 bits of data per cell, TLC flash is the cheapest form of flash to manufacture. The biggest disadvantage to this type of flash is that it is only suitable for consumer usage, and would not be able to meet the standards for industrial use. Read/write life cycles are considerably shorter at 3,000 to 5,000 cycles per cell.


  • Cheapest to manufacture which in turn leads to cheaper to market SSDs.


  • Cells will survive considerably less read/write cycles compared to MLC NAND. This means that TLC flash is good for consumer use only.

Recommended for:

  • Everyday consumer use, web/email machines, netbooks, and tablets.

The SSD Life Cycle

Like all good things, an SSD does not last forever. As noted above, a solid state drive’s life cycle can be directly attributed to the NAND flash it comes with. SLC flash, for example, will last longer than MLC or TLC flash but that comes at a hefty price tag.

With MLC and TLC flash commonly used/found in consumer SSDs, the real question is how long will they last?

TechReport.com has tested several available consumer-grade SSDs, most of which were MLC NAND with one being TLC NAND, and the results are promising. All of the devices tested lasted at least 700 terabytes (TB) of writes before failing, and a couple even pushed passed a petabyte (PB).

This is a lot of data, but let’s put that into perspective in writing 1 PB to an SSD.

1 petabyte (PB) = 1,000 terabytes (TB) / 1,000,000 gigabytes (GB) / 1,000,000,000 (MB)

That 1 PB could net you:

  • 222,222 movie DVDs at 4.5GB a DVD
  • 333,333,333 mp3 songs at 3MB a song
  • 500,000,000 jpg photos at 2MB an image
  • 15,384 installs of the game Grand Theft Auto V at 65GB an install

Looking at those numbers should really put to rest any doubts about your SSD failing in any short amount of time.

If you are considering an MLC or TLC SSD for everyday consumer use like; storing music, photos, software, personal documents or play games then you should feel assured that your SSD should last several years. This kind of usage is considered light compared to the ongoing heavy read/write usage of enterprise servers and computers as outlined in the next section below.

Note: For anyone worried about the lifespan of their SSD, features such as Self-Monitoring Analysis and Reporting Technology, or S.M.A.R.T. for short, can help you better keep track of your SSD’s longevity.

Enterprise vs. Consumer SSDs

Enterprise SSDs are commonly found in database servers.The difference and demands expected of enterprise SSDs set them a world a part from consumer SSDs. Enterprise SSDs are designed to meet a higher standard, and consistently perform in high-tech services, military, science and any area that would require a large amount of reading and writing data.

Database servers are an example of where you might see an enterprise SSDs, these servers are on 24/7 and that includes: longer read/write life cycle, faster read/write speeds, increased reliability and durability in harsh environments.

Consumer SSDs are less expensive, and are stripped down versions of enterprise SSDs. This may sound like you are missing out on certain features, but the benefits of a cheaper product with larger storage capacity are worth it. Besides manufactures are always increasing the performance of SSDs while bringing down the price.

In Conclusion

At this point, you probably have a good idea on the difference between SLC, MLC, and TLC NAND flash. The basics we discussed here, with insight into why some cost more than others, should clear up any confusion as to what type of flash best fits your needs.

Flash Type


Single Level Cell


Multi-Level Cell


Multi-Level Cell


Triple-Level Cell

Read/Write Cycles 90,000-100,000 20,000-30,000 8,000-10,000 3,000-5,000
Bit Per Cell 1 2 2 3
Write Speed ★★★★★ ★★★★☆ ★★★☆☆ ★★☆☆☆
Endurance ★★★★★ ★★★★☆ ★★★☆☆ ★★☆☆☆
Cost ★★★★★ ★★★★☆ ★★★☆☆ ★★☆☆☆
Usage Industrial/Enterprise Industrial/Enterprise Consumer/Gaming Consumer

The important thing to take away from this guide is that modern SSDs are built to last a considerable amount of time. While their life-cycle should be taken into account, it should by no means prevent you from buying faster and more efficient storage.


Comments on Everything You Need to Know About SLC, MLC, & TLC NAND Flash

MyDigitalDiscount.com Friday, January 6, 2017 08:37:59

We have not encountered an eSLC as of yet. SLC flash on its own is a high-grade flash, and low capacity aside is more than suitable for enterprise applications

Frank Thursday, January 5, 2017 13:42:01
How to buy eslc. canot find
Bill Friday, December 30, 2016 08:33:16
A very good explanation written in such a way that a typical computer user can understand the basics without their eyes glazing over. There are several typos which are distracting however.
Midhun Lohidakshan Wednesday, December 7, 2016 02:33:55
Very useful information.Thanks!
Prasad Pattadakal Monday, November 28, 2016 01:12:24
Helpful Article. Easy to understand
Ben Sunday, October 2, 2016 13:24:51
I wonder if it is possible, to overcome the electron lingering problem with TLC, by periodically scheduling,during data wear leveling, to leave each entire block full of zeros for a time, before again re-using it? This would be a form of Tender Loving Care 😉
Sylvain Saturday, October 1, 2016 05:46:05
Thanks for the clean explanation 🙂
Rathlo Friday, September 30, 2016 04:23:52
Just FYI: The conversions from petabytes, terabytes and giogabytes should be 1024 based: 1PB = 1024 TB, 1 TB = 1024 GB, 1GB = 1024 MB.
MyDigitalDiscount.com Wednesday, August 24, 2016 09:59:44

SLC, MLC, and TLC are all considered NAND flash. The difference between the SLC, MLC, and TLC is in their construction and physical design. For this reason, no firmware can change one type of NAND flash to the other.

Firmware updates can improve reliability and performance, so it is always best to consider updates offered from your SSD manufacturer’s website.

Evelyn Wednesday, August 24, 2016 05:11:32
Is the NAND flash used for SLC, MLC and TLC the same? Or the TLC can be converted to SLC thru firmware?
MyDigitalDiscount.com Friday, August 5, 2016 09:52:49
Eric Hoyer,

Thank you, glad it helped. /
Vielen Dank, froh, es half.

Eric Hoyer Friday, August 5, 2016 04:37:02
ist ein guter Beitrag, so kann man erkennen was die leisten und was zu kaufen ist.

Mit freundlichem Gruß
Eric Hoyer


(Google Translate – Ger – Eng)

is a good contribution , so you can see what the make and what to buy .

Eric Hoyer

MyDigitalDiscount.com Friday, March 18, 2016 16:42:23

Thank you for your comment, and your suggestion. SSD lifecycle is something that needs to be understood so that you can continue to operate and secure your data. If you do not have software that monitors your SSD’s status you can always check out Crystal Disk Info. It is a free to use utility found here: http://tinyurl.com/6x7xc3

Going into further detail about the information from Crystal Disk Info with the information provided by an SSD manufacturer would prove for an interesting article.

Ankush Thursday, March 17, 2016 09:44:47
Great article and really helpful. I have already purchased a TLC variant of SSD and was wondering how much time before I would have to part away from my $100. That being said, I never backed up my HDDs till now. I just copied off all the data from my old computers onto the new ones. A comparison of HDD and SSD lives will be appreciated, if you ever get time.

Thanks again.

MyDigitalDiscount.com Wednesday, August 12, 2015 12:50:05

This article serves as an introduction to NAND flash and ignores other components and factors that can affect read/write speed. We are comparing the different flash types against each other, and TLC flash is considered slower in speed vs MLC flash.

The speed difference from a consumer stand point will be minimal or not noticeable

Simon Tuesday, August 11, 2015 20:42:15
There is some incorrect information here.
For example, MLC in itself does not guarantee faster write speeds.

Source : http://www.mydigitaldiscount.com/everything-you-need-to-know-about-slc-mlc-and-tlc-nand-flash.html

[Linux] Cara Mengganti Repository Ubuntu 16.04 LTS dari Server Luar ke Server Lokal

Penjelasan Apa itu Repository?

Saya akan menjelaskan terlebih dulu apa itu repository atau yang biasa dipanggil repo.

Repository adalah tempat disimpannya berbagai aplikasi atau program yang telah dibuat sedemikian rupa sesuai dengan kebutuhan para pengguna linux.

Repository dapat diakses melalui internet, selain dari internet repository juga tersedia dalam bentuk DVD sebagai alternatif jika tidak ada koneksi internet.

Kenapa atau Apa Keuntungan Merubah Repository Ubuntu Server Luar ke Server Lokal?

Kenapa harus mengganti repository ubuntu ke server lokal? atau Apasih keuntungan merubah repository ubuntu ke server lokal?

Jawabannya adalah agar saat proses instalasi program atau aplikasi bisa lebih cepat, karena menggunakan server lokal yang ada didalam negeri bukan server yang ada di luar negeri.

Mengecek Versi Linux Ubuntu yang Digunakan

Sebelum mengganti repository linux ubuntu yang kita gunakan, pastikan dulu versi linux ubuntu-nya. Untuk mengecek versi linux ubuntu, jalankan perintah dibawah ini pada terminal/shell:

$ lsb_release -a

Cara Mengganti Repository Ubuntu

Ada 2 langkah untuk mengganti atau merubah repository ubuntu.

1. Edit File Konfigurasi Repository

Nama file konfigurasi repository ubuntu adalah source.list, lokasi file ini terletak pada direktori /etc/apt/. Untuk mengedit file tersebut kita akan menggunakan editor text nano.

Sebelum melakukan perubahan ada baiknya kita backup dulu file originalnya dengan menjalankan perintah berikut ini:

# cp /etc/apt/source.list /etc/apt/source.list.original

Setelah melakukan proses backup, dilanjutkan dengan mengedit file source.list. Disini kita akan menggunakan editor text nano.

# nano /etc/apt/source.list

Setelah file dibuka, hapus semua isi file tersebut lalu ganti dengan repositoy lokal ubuntu 16. Anda dapat melihatnya di dalam artikel ini.

Contoh kita menggunakan repository lokal ubuntu 16.04 via Kambing UI maka isi file source.list akan terlihat seperti ini:

deb http://kambing.ui.ac.id/ubuntu/ xenial main restricted universe multiverse
deb http://kambing.ui.ac.id/ubuntu/ xenial-updates main restricted universe multivers
deb http://kambing.ui.ac.id/ubuntu/ xenial-security main restricted universe multivers
deb http://kambing.ui.ac.id/ubuntu/ xenial-backports main restricted universe multivers
deb http://kambing.ui.ac.id/ubuntu/ xenial-proposed main restricted universe multiverse

Setelah itu Save dengan menekan tombol Ctrl+O, lalu Exit dengan menekan tombol Ctrl+X.

Untuk mengganti atau merubah isi file source.list kita perlu masuk ke dalam mode superuser atau root.

2. Update Repository Ubuntu

Proses update diperlukan setelah merubah repository, agar linux ubuntu yang kita gunakan langsung mengenali server mana yang akan dipakai nantinya untuk proses update maupun install aplikasi atau program.

Berikut ini perintah update-nya:

# apt-get update

Selesai. cheers 😀

Source : http://cubnetwork.com/cara-mengganti-repository-ubuntu-16-04/

[Linux] Apa itu Swappiness ?

Pada saat menginstall linux, pasti ada notice untuk pemakaian swap space. swap space digunakan jika penggunaan memori fisik ( RAM ) telah penuh yang digunakan oleh proses yang sedang berjalan. Dan biasanya perhitungan untuk ukuran partisi swap space itu 2 kali lipat dari ram. Contoh : Laptop anda memiliki 1 GB ram, maka swap space anda minimal 2 GB ( ini perhitungan naif, posting selanjutnya akan dibahas bagaimana cara akurat untuk menentukan ukuran swap space ).

Apa itu swappiness ?

pemakaian swap space oleh sistem juga ada perhitungannya, tidak asal RAM penuh lalu langsung memakai swap soace. Ada istilah swappiness. swappiness adalah parameter pada kernel linux untuk menentukan kapan swap space itu dipakai. swappiness ini juga salah satu faktor penentu performa suatu OS Linux. paramater swappiness default nya 60. dan bisa di ubah dari 10 sampai 100.

Bagaimana mengubah nya ?

untuk mengubah parameter swappiness ada 2 cara, yang pertama dengan mengubah di /proc/sys/vm/swappiness. jika belum diubah isi dari file tersebut “60”. tinggal edit menggunakan nano atau vi atau yang lain editor favorit anda. cara kedua menggunakan perintah langsung, “sudo sysctl vm.swappiness=10” berarti anda mengubah parameter swappiness menjadi “10”. nah bagaimana cara perhitungan swappiness nya ? tadi kita mengubah nya jadi 10. maka jika penggunaan RAM mencapai 90%, swap space akan dipakai oleh sistem. nah jadi default nya kan 60, maka jika penggunaan RAM mencapai 40%, swap space akan dipakai.

Wajib kah pemakain swap space ?

inget, swap space menggunakan space harddisk. sedangkan latency harddisk itu lebih buruk daripada RAM. Jadi performa akan menurun jika proses pindah ke swap space. maka kalau anda mempunyai RAM yang cukup lumayan besar, maka parameter swappiness “10” aman untuk digunakan. hindari lah penggunaan swap space sekecil mungkin demi performa proses anda.

Source : http://cubnetwork.com/apa-itu-swappiness/