You are reading the article Understanding The Sysrq Key – The Magic Key To Control Linux updated in December 2023 on the website Katfastfood.com. We hope that the information we have shared is helpful to you. If you find the content interesting and meaningful, please share it with your friends and continue to follow and support us for the latest updates. Suggested January 2024 Understanding The Sysrq Key – The Magic Key To Control Linux
How To Activate The Magic KeyAs said before, the magic key is super handy. But first, you have to activate this functionality if it is not already done. To check, use the command
cat
/
proc/
sys/
kernel/
sysrqIf it returns a 1, the Magic Key is working. If it is a 0, you will need to activate it. In most cases, if you want to activate it temporarily, you can try
sudo
sysctl kernel.sysrq=1
Note that this will be only temporary. If you want the Magic Key to work even after a reboot, the best way is to edit the file “/etc/sysctl.conf”, so that the line
kernel.sysrq =0
becomes
kernel.sysrq =1
List of Useful CombinationsThe whole point of using the Magic SysRq key is to combine it with the “Alt” key and another letter in order to trigger a particular function, even if your computer seems frozen. To begin, you should know that this System Request key is usually sharing its location with the “Print Scrn” key at the top right of your keyboard. Above the “Insert” key, and left to “Scroll Lock.”
As you can guess, the effect of the combination depends on which letter key is used. Here is a non-exhaustive list of letter you can use to obtain an interesting result.
b – reboots the computer
e – ask all processes to terminate gracefully
f – to get rid of an Out Of Memory condition via oom_kills
i – to kill all processes immediately except init
k – to kill absolutely all processes, including X
m – to output the current memory information
o – to shut down the computer
r – very useful, to take the keyboard out of the X server control
s – to sync data from all mounted devices (avoid data loss in case of violent reboot)
t – to display a list of the current tasks
u – to remount all file system in read-only mode
Famous ExamplesEvery Linux user should know these examples. If your X server is frozen and you cannot access any virtual console, using “Alt + SysRq + r” should take the keyboard away from the X server and let you perform “Ctrl + Alt + F1” in order to get to a terminal and kill the appropriate processes.
If you do not have the patience to do that, “Alt + SysRq + k” will kill everything in the same way as “Ctrl + Alt + Backspace” (but more violently).
If nothing responds at all, and the only way is to reboot your computer, the classical combo is “reisub” for “Raising Elephant Is So Utterly Boring”, or just remember the opposite of “busier“. Use each letter of this anagram with the magic key in order to:
Take the keyboard from X
Ask all programs to end gently
Kill the one who did not
Save the data from the cache to the hard drive
Remounts the file systems
Reboot
ConclusionThe idea is that the magic key combinations are generally super violent. You do not want anybody to use it on your computer while you are not looking. But as a last resort, it can become the ultimate tool. I rarely encountered a situation where SysRq did not respond. So when your Linux does not obey its master, you know what to do.
Image credit: SysRq
Adrien
Adrien is a young but passionate Linux aficionado. Command line, encryption, obscure distributions… you name it, he tried it. Always improving his system, he encountered multiple tricks and hacks and is ready to share them. Best things in the world? Math, computers and peanut butter!
Subscribe to our newsletter!
Our latest tutorials delivered straight to your inbox
Sign up for all newsletters.
By signing up, you agree to our Privacy Policy and European users agree to the data transfer policy. We will not share your data and you can unsubscribe at any time.
You're reading Understanding The Sysrq Key – The Magic Key To Control Linux
The Key To Diversity Is In Human Connection
We’ve all stood witness to a very interesting, cultural shift across the tech landscape in the US recently. At this point, the lack of diversity in tech isn’t news, but we’ve perhaps reached a tipping point where people have stopped talking about it and actually started doing something to fix it.
Case in point: Wayne Sutton is helping African Americans tell their stories, some of the strongest entrepreneurs up in the Bay Area are women, and the White House just held their first ever Demo Day to celebrate diversity in tech.
Even so, it’s an unfortunate and undeniable fact that underserved and underrepresented groups still face biases and harassment, even today. It raises a question many of us have probably asked at one point: why do they still face these issues?
Stacy Parson is the Principal at Knowetry Consulting, and she’s spent a long time studying both psychology and business, both codependent and dependent of one another. Further, it’s given her a keen insight to answer the question posed.
“I think of diversity in terms of the way we allow different ideas to affect us. We as humans are built to resist these new ideas, but at the same time people need to understand them so they can, in turn, understand more about the world,” says Parson.
This is actually one of the core pillars of her work at Knowetry. By helping individuals confront their fear and uncertainty of new ideas she can help them successfully operate in the realm of the unknown: interesting given that entrepreneurs live in the unknown.
That is, uncertainty will always be a part of life, so you have to learn to embrace it. Parson sees underserved and underrepresented groups as an embodiment of this uncertainty, in a way, and thus something to be embraced.
As she tells it, on a psychological level humans have a kneejerk reaction to avoid anything that breaks their paradigm of habit and familiarity. However, what’s really important here is how you defeat the inertia behind this reaction.
For Parson, it’s all about properly equipping yourself.
“It’s essentially about understanding what creates friction and being able to name those issues, address them, and reduce friction for effective output,” says Parson. “Uniqueness creates difference, and that difference, if misunderstood, creates friction. Issues usually boil down to people and perspective.”
For example, a startup company that has to shift their company culture after the ball has started rolling is going to have a difficult time. Parson believes that entrepreneurs are always better off capturing a sustainable culture of diversity from square one, especially when it comes to diverse peoples, ideas, and opinions.
It’s a sentiment that Melinda Briana Epler, CEO of Change Catalyst, would agree with implicitly. She would also point out that this lack of diversity is heavily embedded in a heteronormative leadership structure.
To that end Epler has spent countless hours researching and implementing ways to build strong female tech leaders from the ground up. Specifically, her research showed accelerators as one of the best ways to do this, but women are still the most underserved and underrepresented group across accelerators.
“There aren’t enough women leaders, innovators who are given the chance to get their work out there. The same applies for any underserved and underrepresented group,” says Epler. “I’ve always felt the need to make the world a better place. There are so many things that need to change in our world and I want to do as much as I can in the short time I have to make a difference.”
It’s why she’s spent her time recently building an online accelerator that offers all of the amenities of an in-person option – not to mention it’s an untapped goldmine for a startup. According to Epler, not everybody is going to be able to spend two to three months apart from their family, especially women who are the primary caregivers to their children.
It’s an empathetic outlook, something Epler developed back in high school when she participated in an exchange program with the USSR. One year their students would come to America, the next year US to the Soviet Union – mind you, this was during the Cold War and prejudices were running high.
“A group of Soviet students came here and I realized that people might not be able to speak the same language, but we can communicate in other ways. I don’t get why people would want to blow each other up,” Epler recalls.
You might say this was her “aha moment”, when she realized that being human was about human connection. This connection creates empathy between us, she explains.
The roots of this idea grew strong and mighty when she embarked on her trip to the USSR, expecting the worst only to be greeted by a friendly community of kids just like her.
“This exchange motivated me to look at diversity issues and really learn how to create empathy and compassion in a way that would destroy the problem,” explains Epler.
People, as she says, are simply people, wherever you go.
I think that’s the real crux of the issue here arrives at the intersection of human connection. If we can take one thing away from these dynamic, incredibly poignant women let it be this: face your uncertainty and always connect with new people, ideas, and thoughts.
Honestly, this is an issue that both Epler and Parson could talk about all day, and I could listen contentedly. It’s actually why we’ve invited both of them to join us at our Celebrate Conference in Downtown Las Vegas this year. They’ll each be leading workshops on embedding a healthy culture of diversity into the core of a startup.
As individuals, operating alone, we are strong. Together, operating as a unit, we are unstoppable and can legitimately change the world for underserved and underrepresented groups. Come by and help us celebrate diversity in tech together.
Image Credit: Pixabay
Find Your Windows 10 Product Key The Easy Way
Every licensed copy of Windows 10 has a unique license key and if you ever need to reinstall Windows, you’ll potentially need to find the Windows 10 product key to get things back up and running again.
The problem is that most people have never even seen their key, since they bought a computer with Windows preloaded. You may also have lost yours or forgot what you did with it. The good news is that there are many different ways to figure out what license key is yours.
Table of Contents
Also, be sure to check out our short video on our YouTube channel that walks you through the info we have written about in this article.
But First, Some Things You Should KnowYour Windows 10 product key is not locked to any sort of specific Windows 10 media. If you’ve lost your disc or flash drive with Windows 10, you can simply download a new copy and install from that. The key is simply a representation of your license.
Your Windows 10 license is also locked to a particular computer’s hardware. If you make a big hardware change, or change computers entirely, then you’ll have to do a reactivation so bind your license to the new hardware configuration. If Microsoft thinks you are abusing your license by installing Windows 10 to multiple machines at the same time, they may be unwilling to do this.
You Might Not Need ItIf you have a Microsoft Account and have previously linked it to your Windows 10 product key, all you have to do on a new install is log in with your account details. Check out this article on how to link your product key to see how it works.
When you switch from a “local account” to logging in with your Microsoft Account, this probably happened automatically. If you are trying to activate a copy of Windows, simply change your account from local to Microsoft and it should work.
The same applies if you upgraded a copy of Windows 7 or 8, for which you would have needed a Microsoft Account. Simply log into Windows with your account credentials, since there is no product key involved here either.
Check Your Retail BoxThis is very obvious, we know. Still it should be mentioned since, if you bought a boxed retail Windows 10 copy, this is the simplest way to find the Windows 10 product key. It should be inside the box printed on something.
Get It Straight From Windows Check Your Computer for a StickerIf you bought a pre-built computer or laptop which came with Windows 10, check the chassis for a sticker which displays the Windows 10 product key. This is becoming less common with high-end laptops such as unibody ultrabooks, but plenty of computers still display their product keys on a sticker.
Check The Documents That Came With Your PCIf there’s no sticker in sight, there might be a certificate of authenticity in the document pack that came with your computer. Assuming that you didn’t throw all of those little pamphlets out, you might be lucky and find your product key in between the offers for antivirus packages and peripherals.
Use a Third-Party ToolOne of the easiest ways to retrieve your product key from a running machine is to use a third-party utility. Produkey worked perfectly for us on the latest version of Windows 10. Just run the program and your product key is right there.
Do note that some anti-malware packages will flag Produkey as a “PUP” or potentially unwanted program. It’s not a virus or anything harmful to your system, a PUP is just a tool that could be used by hackers to compromise your machine. However, this is your computer, so there’s nothing wrong with you using the tool to retrieve the key you already paid for.
Digital Store RecordsIf you bought your copy of Windows 10 through a digital storefront such as Amazon or the Microsoft Store, they’ll have a record of your product key. It will either be in the email you were sent confirming the purchase or in your order history, should you have deleted that email. So all you have to do is search your mailbox or log into your online account.
Hit Up The OEMIf you bought a pre-built computer or laptop that came with Windows, then you probably have an OEM (original equipment manufacturer) Windows license. This opens up the possibility that your OEM will know which product key goes with your computer’s serial number.
There’s no guarantee that they’ll have this information on hand for you, but if you’ve come this far down the list then it’s not the worst option.
The Last Resort: Call MicrosoftOK, this might not really be a last resort. While there have been ups and downs over the years, Microsoft’s online customer service was quite good the last few times we’ve had to deal with them. So if you do have problems activating Windows or finding your Windows 10 product key, there’s a good chance hopping on live chat with one of their service representatives will solve the issue.
Are You The Keymaster?Product license keys are obviously on the way out when it comes to Windows, as Microsoft starts shifting to a cloud-based subscription model for its software and services.
For now however, we still have to occasionally deal with the minor road block of not having a Windows key in hand. The worst case scenario is being forced to buy a whole new Windows license, but hopefully the tips above will help you avoid that.
What Is A Network Security Key?
Last Updated on June 14, 2023
The rise of the internet has made users have more access to information than ever before. While there are tremendous benefits to this, including convenience, there has also been an increase in cyber threats.
Network security keys minimize this risk, helping protect those who use the internet.
What is the Network Security Key on a Router?Put simply, a network security key is basically a password. These passwords are needed in order to access a certain network. They are put in place to prevent unauthorized access to specific networks.
For example, to connect to the Wi-Fi network in your home, you should have a password that needs to be entered in order to have access to it. This enables you to have a secure connection and prevents unauthorized access.
The same goes for any other establishments you visit, like restaurants, stores, and airports. Enabling passwords in order to gain access to networks makes it difficult for cyberattacks to happen. While some experienced hackers may still be able to get access, this is highly reduced when there is a secure network security key enabled.
Benefits Of Network Security KeysAs mentioned, network security keys help keep any digital users’ information safe and secure. Security keys have certain encryption standards which prevent hackers from being able to access any user’s information.
These keys also keep all identities hidden, preventing any hackers from being able to find out who accessed what networks and when.
Online Threats Prevented From Network Security KeysUnsecured wireless networks are susceptible to a variety of online threats, whether it’s a home network or a business. Below are a few of these risks:
PiggybackingPiggybacking can occur when someone is able to connect to an unsecured network when they are within range of it. This means that any neighbors could connect to someone’s network if it isn’t secure.
Users who connect to this network then have the ability to perform illegal online activities such as accessing credit card information, and other personal files.
Evil Twin AttacksEvil twin attacks are more calculated than piggybacking. This is when users gain information on a public network in order to set up one that impersonates it. The impersonated signal is then made to have a stronger signal than the original, so users then end up connecting using the stronger network.
As users are then connected to the attacker’s network, these attackers are able to use tools in order to read the information that users send through the internet. This is especially dangerous if any online payments are completed using this network, as it can give the attackers credit card information.
The same goes for any passwords and login details for certain websites.
Final ThoughtsTo conclude, network security keys are passwords or codes that need to be entered in order to gain access to a certain network.
These keys are made to be secure along with encryption standards that protect any information from users who have connected to that network.
Having a wireless internet connection without a network security key can expose users to a variety of online threats, some of which involve hackers gaining access to data and personal files, including credit card information.
Caution must also be taken when connecting to public networks, as hackers have the ability to mimic these in order to steal information.
This article has outlined the importance of network security keys, and the threats involved when they are not utilized correctly.
Men’S Hockey Terriers: Continuity Is Key
Men’s Hockey Terriers: Continuity Is Key As season begins, experience is on their side
Chris Connolly (MET’12) is one of only five Terrier hockey players remaining from BU’s NCAA championship 2008–2009 team. Photo by Steve McLaughlin/BU Athletics
The BU men’s ice hockey team launches its season tomorrow night with a bull’s-eye on its back. The Terriers are ranked 6th in the country by USA Today and 10th by United States College Hockey Online.
Their home opener against the University of New Hampshire Wildcats will be the start of what promises to be a fiercely competitive Hockey East battle. But that’s not the only challenge. The Terriers’ schedule is relentless. And they have the task of recovering from the 2010–2011 season, when the team, one of the youngest in the program’s history, came up short.
But the 2011–2012 squad has something that last year’s team sorely lacked: experience.
“We’re comfortable with each other, there’s a lot of camaraderie in the locker room, and we’re a tight-knit group off the ice as well,” says captain Chris Connolly (MET’12). “Being that much older and being more mature can only help us this season.”
Connolly, one of only five players remaining from BU’s NCAA championship 2008–2009 team, says last year’s 19-12-8 record was a decent outcome given the team’s youth. But he was disappointed by the Terriers’ failure to make the NCAA tournament and their elimination in the Hockey East quarterfinals at the hands of Northeastern.
“The ultimate goal is to get back on top and win a national championship, because there’s nothing that compares to that feeling,” Connolly says. “At the same time, I just want to be able to improve on last year and take a step in the right direction.”
Head hockey coach Jack Parker (SMG’68, Hon.’97) concurs with Connolly’s assessment.
“It was a solid year for us because we were third in Hockey East, with a young team in a difficult league, but we didn’t go anywhere near where we’d like to,” Parker says.
Among this season’s returning players are all seven of the Terriers’ top scorers from last year and five of their six most experienced defenders.
Connolly was captain last year also, so he’s familiar with the role. He’s the first two-year captain since Jack O’Callahan (CAS’79), a member of the legendary “Miracle on Ice” U.S. Olympic team that won a gold medal in 1980. Connolly finished last season tied for second on the team in points, with 28, trailing only newly appointed assistant captain Alex Chiasson (CAS’13).
Forward Charlie Coyle (CGS’12), last year’s Hockey East Rookie of the Year, was drafted 28th overall by the San Jose Sharks in 2010 and has been listed as the 20th-best prospect in the National Hockey League by the site Hockey’s Future. And top goalie Kieran Millan (MET’12), a runner up for Hockey East Player of the Year honors last season, returns as well. Millan, a 2009 draftee of the Colorado Avalanche, holds BU’s single-season record for saves and was named the Terriers’ Most Valuable Player last season.
Beyond the Terriers’ stars, there is no lack of talent on this season’s team. Of the 26 players on the roster, 13 are NHL draftees, and a 14th—Ben Rosen (CAS’13)—was invited to the New York Islanders minicamp earlier this year.
Parker says that while talent is obviously important, it’s only one of the factors that will determine the team’s success this season. “Talent doesn’t win,” Parker says. “There’s not a team in this league that doesn’t have talent. Attitude and effort are what win in this league.”
Connolly agrees, and says that what will determine the Terriers’ success is how well they play in late winter and spring. “We have to make sure our team is playing our best hockey at the end of the year, and that’s something that’s hard to achieve,” he says. “It usually works out that the team with the older players can make more of a run come playoff time. Hopefully we’re playing our best hockey come April.”
Parker says he is confident that the Terriers will be able to maintain a high level of play all season.
“Last year’s team was the youngest team I’ve ever coached, both as far as class year and age,” he says. “We had 17- and 18-year-olds playing against 24- and 25-year-olds, and the long season wore on them. Some who had great starts fizzled at the end. But I think the best thing that happened to us is that we got older this summer. We’ve been through the war a bit, and that in and of itself will make us a better team.”
The Terriers begin their season tomorrow, Saturday, October 8, when they take on the University of New Hampshire Wildcats at 8 p.m. at Agganis Arena. Tickets are $19 for BU students, faculty, and staff, and $26 for the public. Tickets may be purchased ahead of time here or at the Agganis Arena ticket office.
Ben Carsley can be reached at [email protected].
Explore Related Topics:
Python Dictionary Append: How To Add Key/Value Pair
Dictionary is one of the important data types available in Python. The data in a dictionary is stored as a key/value pair. It is separated by a colon(:), and the key/value pair is separated by comma(,).
Dictionary is one of the important data types available in Python. The data in a dictionary is stored as a key/value pair. It is separated by a colon(:), and the key/value pair is separated by comma(,).
The keys in a dictionary are unique and can be a string, integer, tuple, etc. The values can be a list or list within a list, numbers, string, etc.
Here is an example of a dictionary:
my_dict = {"a": A, "b": B, "c": C, "d": D}Restrictions on Key Dictionaries
Here is a list of restrictions on the key in a dictionary:
If there is a duplicate key defined in a dictionary, the last is considered. For example consider dictionary my_dict = {“Name”:”ABC”,”Address”:”Mumbai”,”Age”:30, “Name”: “XYZ”};. It has a key “Name” defined twice with value as ABC and XYZ. The preference will be given to the last one defined, i.e., “Name”: “XYZ.”
The data-type for your key can be a number, string, float, boolean, tuples, built-in objects like class and functions. For example my_dict = {bin:”001″, hex:”6″ ,10:”ten”, bool:”1″, float:”12.8″, int:1, False:’0′};Only thing that is not allowed is, you cannot defined a key in square brackets for example my_dict = {[“Name”]:”ABC”,”Address”:”Mumbai”,”Age”:30};
How to append an element to a key in a dictionary with Python?We can make use of the built-in function append() to add elements to the keys in the dictionary. To add element using append() to the dictionary, we have first to find the key to which we need to append to.
Consider you have a dictionary as follows:
my_dict = {"Name":[],"Address":[],"Age":[]};The keys in the dictionary are Name, Address and Age. Usingappend() methodwe canupdate the values for the keys in the dictionary.
my_dict = {"Name":[],"Address":[],"Age":[]}; my_dict["Name"].append("Guru") my_dict["Address"].append("Mumbai") my_dict["Age"].append(30) print(my_dict)When we print the dictionary after updating the values, the output is as follows:
Output:
{'Name': ['Guru'], 'Address': ['Mumbai'], 'Age': [30]} Accessing elements of a dictionaryThe data inside a dictionary is available in a key/value pair. To access the elements from a dictionary, you need to use square brackets ([‘key’]) with the key inside it.
Here is an example that shows to accesselements from the dictionary by using the key in the square bracket.
print(“username :”, my_dict[‘username’]) print(“email : “, my_dict[“email”]) print(“location : “, my_dict[“location”])
Output:
username : XYZ location : MumbaiIf you try to use a key that is not existing in the dictionary , it will throw an error as shown below:
print(“name :”, my_dict[‘name’])
Output:
Traceback (most recent call last): print("name :", my_dict['name']) KeyError: 'name' Deleting element(s) in a dictionaryTo delete an element from a dictionary, you have to make use of the del keyword.
The syntax is :
del dict['yourkey'] # This will remove the element with your key.To delete the entire dictionary, you again can make use of the del keyword as shown below:
del my_dict # this will delete the dictionary with name my_dictTo just empty the dictionary or clear the contents inside the dictionary you can makeuse of clear() method on your dictionaryas shown below:
your_dict.clear()Here is a working example that shows the deletion of element, to clear the dict contents and to delete entire dictionary.
del my_dict[‘username’] # it will remove “username”: “XYZ” from my_dict print(my_dict) my_dict.clear() # till will make the dictionarymy_dictempty print(my_dict) delmy_dict # this will delete the dictionarymy_dict print(my_dict)
Output:
{} Traceback (most recent call last): print(my_dict) NameError: name ‘my_dict’ is not defined
Deleting Element(s) from dictionary using pop() methodIn addition to the del keyword, you can also make use of dict.pop() method to remove an element from the dictionary. The pop() is a built-in method available with a dictionary that helps to delete the element based on the key given.
Syntax:
dict.pop(key, defaultvalue)The pop() method returns the element removed for the given key, and if the given key is not present, it will return the defaultvalue. If the defaultvalue is not given and the key is not present in the dictionary, it will throw an error.
Here is a working example that shows using of dict.pop() to delete an element.
my_dict.pop(“username”) print(my_dict)
Output:
Appending element(s) to a dictionaryTo append an element to an existing dictionary, you have to use the dictionary name followed by square brackets with the key name and assign a value to it.
Here is an example of the same:
my_dict[‘name’]=’Nick’
print(my_dict)
Output:
Updating existing element(s) in a dictionaryTo update the existing elements inside a dictionary, you need a reference to the key you want the value to be updated.
We would like to update the username from XYZ to ABC . Here is an example that shows how you can update it.
my_dict[“username”] = “ABC”
print(my_dict)
Output:
Insert a dictionary into another dictionaryConsider you have two dictionaries as shown below:
Dictionary 1:
Dictionary 2:
my_dict1 = {"firstName" : "Nick", "lastName": "Price"}Now I want my_dict1 dictionary to be inserted into my_dict dictionary. To do that lets create a key called “name” in my_dict and assign my_dict1 dictionary to it.
Here is a working example that shows inserting my_dict1 dictionary into my_dict.
my_dict1 = {“firstName” : “Nick”, “lastName”: “Price”}
my_dict[“name”] = my_dict1
print(my_dict)
Output:
Now if you see the key “name”, it has the dictionary my_dict1.
Summary
Dictionary is one of the important data types available in Python. The data in a dictionary is stored as a key/value pair. The key/value is separated by a colon(:), and the key/value pair is separated by comma(,). The keys in a dictionary are unique and can be a string, integer, tuple, etc. The values can be a list or list within a list, numbers, string, etc. When working with lists, you might want to sort them. In that case, you can learn more about Python list sorting in this informative article.
Important built-in methods on a dictionary:
Method Description
clear() It will remove all the elements from the dictionary.
append() It is a built-in function in Python that helps to update the values for the keys in the dictionary.
update() The update() method will help us to merge one dictionary with another.
pop() Removes the element from the dictionary.
Update the detailed information about Understanding The Sysrq Key – The Magic Key To Control Linux on the Katfastfood.com website. We hope the article's content will meet your needs, and we will regularly update the information to provide you with the fastest and most accurate information. Have a great day!