Systemd, the Linux world’s favorite init monolith, can be potentially crashed or hijacked by malicious DNS servers. Patches are available to address the security flaw, and should be installed ASAP if you’re affected.
Continue reading Systemd Vulnerable to DNS Attacks
Most people connect to the internet via their ISP’s DNS servers which more than likely are not the best and more than likely is slowing down your browsing. Using a 3rd party service not only speeds up your experience online. A while ago we wrote about OpenDNS, today we’re going over Google’s DNS service.
Make sure to write down your ISP’s DNS servers.
Google Public DNS IP addresses
IPv4 addresses are as follows:
IPv6 addresses are as follows:
Making the changes
- Start the
Network and Sharing Center (this process varies by windows version)
Change adadpter settings
Local Area Connection or
Wireless Network Connection slelect
- Type in your administrator password if you are promted for it.
- Click the
- Under the
Internet Protocol Version 4 (TCP/IPv4) or
Internet Protocol Version 6 (TCP/IPv6) and click
Advanced and select the
DNS tab, write down any IP’s that are listed here for future reference in case you want to revert later on.
Use the following DNS server addresses
- Enter the IP’s from above
- Restart your computer
- Click the Apple menu ()
System Preferences and click the
- Select the connection you want to configure (
Thunderbolt Ethernet or
Display Ethernet) then click
- Select the
- Click the
+ icon to enter the IP Addresses (repeat for each address)
Apply then click
I will go over doing this in Ubuntu since that is one of the more common flavors.
System Preferences and click
- Select the connection you want to configure
Wireless tab, then select the appropriate network.
Edit, and in the window that appears, select the
IPv4 Settings or
IPv6 Settings tab.
- If the selected method is
Automatic (DHCP), open the dropdown and select
Automatic (STATIC) addresses only instead.
- If the method is set to something else, do not change it.
- In the DNS servers field, enter the IP addresses, separated by a space:
- If you are prompted for a password or confirmation, type the password or provide confirmation.
If your distribution doesn’t use Network Manager, your DNS settings are specified in
sudo vi /etc/resolv.conf
If any nameserver lines appear, write down the IP addresses for future reference. Replace or add, the following lines:
Save and exit
Restart any Internet clients you are using.
sudo /etc/init.d/networking restart
Every router uses a different user interface for configuring DNS server settings; we provide only a generic procedure below. For more information, please consult your router documentation.
Some ISPs hard-code their DNS servers into the equipment they provide; if you are using such a device, you will not be able to configure it. Instead, you can configure each of the computers connected to the router, as described above.
- In your browser, enter the IP address to access the router’s administration console.
- When prompted, enter the password to access network settings.
- Find the screen in which DNS server settings are specified.
- If there are IP addresses specified in the fields for the primary and seconday DNS servers, write them down for future reference.
- Replace those addresses with the IP addresses from above
- Save and exit.
- Restart your browser.
Ok folks, after many moons trying to fix this issue in Yosemite I finally got it… If you are running earlier versions of OSX, see here for the fix.
What am I talking about?
Append search domains for partially qualified domain names when performing DNS lookups. You know.. For example, you work in it and ssh to hosts regularly and your company uses
hostname.domain.com but you want to ssh to
hostname.sub to shave some time off your clock. With older versions you could apply a fix with mDNSResponder to work around whatever Apple decided to do there; around rolls Yosemite and they change the whole damn thing around. Continue reading Fix for broken search domain resolution in OS X Yosemite
We all have had that one time when your computer refuses to go to a site, or you can’t connect to something or a network. This is a result of a bad IP address or some other DNS result being cached in your system.
What is DNS caching
At it’s basic, DNS cache is simply how your computer remembers sites or networked locations and devices you’ve visited or networks you’ve connected to. It basically keeps the address that matches the URL of a site you visited for example.
How to flush
Flushing your DNS cache basically clears out all entries from your system and allows new entries to be made so that things flow smoothly. So here is how to do it on different systems.
Depending on the version of Windows you are using, the process to bring up a Command Prompt will be different but that is what you need. Basically you will want to do the following:
- For XP – Click Start -> In the Run box type cmd.exe and press Enter
- For 7 – Click Start -> All Programs -> Accessories -> right click on Command Prompt and click Run as Administrator
- Win8 and up – Simply type cmd which will bring up the search results to the right of your screen -> right click on Command Prompt and click on Run as Administrator
- Type ipconfig /flushdns and press Enter
- Open a command terminal and run the following:
- 10.8 Mountain Lion – sudo killall -HUP mDNSResponder then
- 10.9 Mavericks and up – dscacheutil -flushcache then sudo killall -HUP mDNSResponder
Open a terminal and run the following sudo dscacheutil -flushcache
If you ever need to clear your DNS cache on your Mac you’ve come to the right place.
DNS is cached on your machine to help speed things up as you browse the same pages, servers, sites, etc by keeping a cache so you don’t have to go through the entire process again every time you visit the same place. Sometimes tho, things get lost in translation and a bad cache or two remain lingering causing troubles for you. Fear not, your SuperHero is here to save the day.
Clearing cache on Yosemite
Open Terminal and run this command:
Clearing cache on Mavericks
Open Terminal and run this command:
To reload DNS type this command:
sudo killall -HUP mDNSResponder
Clearing cache on older versions
Open Terminal and run this command:
IPs to Websites
Here is a list of IPs to use in the event of a DNS takedown. We will be adding more as time rolls by. If you have others to share, please leave a comment.
- Here’s a tip for the do-it-yourself crowd: Go to your computer’s Start menu, and either go to “run” or just search for “cmd.” Open it up, and type in “ping [website address],”
- Once you have the IP for a website, all you really need to do is enter it like you would a normal URL and hit enter/press go. Typing in “184.108.40.206” should bring you to the front page of AO3, for example, just as typing “220.127.116.11/dashboard” should bring you straight to your Tumblr dashboard. Since we’re obviously bracing for the worst case scenario which would involve you not being able to access the internet regularly, you should, save this list.
OpenDNS is an online service that offers many features that your ISP will not provide to you through their DNS servers. As the title states this service will make your web time safer and faster and it’s free. Follow the instructions below to get going.
Here is a quick list of things you will have:
- DNS Infrastructure – OpenDNS has data-centers all over the world thus will provide you with robust routing. It is smart enough to route you to it’s closest data-center resulting in faster connection to the sites you visit. It also uses SmartCache, a feature that caches the last known working route to a website so when most people can’t get to a site you will be able to.
- Control – You will be able to filter what content gets to and from your computers. You can either allow or block things like P2P, proxies, adult and more and you can block the tools known to bypass most filters. You can whitelist or blacklist up to 25 domains and point these to a particular site of your choosing.
- Security – You are protected against phishing attacks and botnets.
- Insights and reporting – You can see reports about traffic on your network via detailed charts and statistics, you will have access to the last two weeks of data.
- Typo correction – Checks for and corrects the most common typos in top-level domains like .com, .net and .org.
- Shortcuts – Allows you to create a custom shortcut for a log url by using a short url alias.
Continue reading OpenDNS for a faster more secure web experience