How to configure interface bonding to bound to 2 eth interfaces together in Linux, specifically CentOS/RHEL? This tutorial Configuring Interface Bonding on CentOS/RHEL/OEL 6.x introduces setting up interface bonding well on CentOS / RHEL / OEL 6.
Category: Tutorial
How to resolve a domain name from a specific DNS server instead of the configured one in Linux?
Posted onI would like to check whether the domain name’s IP has changed in the authoritative DNS server. The system’s configured DNS server may still cache the old IP, which is fine. The question is how to query from the authoritative DNS server the new IP? You can use dig – DNS lookup utility to query
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HDFS stays in safe mode because of reported blocks not reaching 0.9990 of total blocks
Posted onAfter a node failure and restarting the HDFS, the NameNode reports: “The reported blocks 1968810 needs additional 5071 blocks to reach the threshold 0.9990 of total blocks 1975856. Safe mode will be turned off automatically.” in the log. Why this happens? And how to fix it? About why the NameNode stays in the safe mode:
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Any good Web browser in command line in Linux?
Posted onWhat suggested web browser in command line? This will be very useful for browsing the Internet from a command line via SSH. You may use Lynx, a fully-featured World Wide Web (WWW) client for users running cursor-addressable, character-cell display devices, in Linux. Homepage: http://lynx.isc.org/ Lynx is a fully-featured World Wide Web (WWW) client for users
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How to reset iOS / iPhone password?
Posted onI host lost the password of my iPhone. How to erase or reset it? Check Forgot passcode for your iPhone, iPad, or iPod touch, or your device is disabled from Apple for how to reset the passcode. As all methods will erase your iPhone, the “Recovery mode” method may be the most easier and reliable
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How to disable the coredump function of systemd on Linux?
Posted onI do not want to have coredump for the developing machine using systemd on Linux? How to disable the coredump function of systemd? You can disable coredump function of systemd by adding this line Storage=none to /etc/systemd/coredump.conf For your reference: Storage= Controls where to store cores. One of “none”, “external”, “journal”, and “both”. When “none”,
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Un-exporting an Exported Variable in Bash in Linux
Posted onHow to un-export an imported variable in Bash on Linux? For example, first, I export a variable MODE like export MODE=debug but I want to unexport the MODE (not turn to be `””`, should be truly non-defined). You can export -n MODE or unset MODE For your reference (from the [`bash` manual](https://www.systutorials.com/docs/linux/man/1-bash/)): export [-fn] [name[=word]]
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How to use iPhone to browse blocked websites in mainland China?
Posted onHow to use iPhone to browse blocked websites in mainland China? FYI: on iPhone, these 2 Apps are the favorite combination I am using for visiting blocked websites in mainland China: Check OpenVPN + Ovpn Spider: Free VPNs for iPhone Users for how to use them together. OpenVPN is for setting up OpenVPN VPN connection.
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Maximum allowed file path length for C programming on Linux?
Posted onWhen programming in C on Linux, it is common to allocate a buffer for storing the full path of a file. How to get a safe maximum size for allocating buffers for file paths? The header <linux/limits.h> includes macros for the path and file name length limits. On my system (Fedora 21), it is located
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How to automatically post blog RSS feed to Google plus pages?
Posted onI have a blog with RSS feeds. Feeding to twitter and facebook is supported by many tools. But for the Google plus page, it seems not straightforward. How to automatically post blog RSS feed to Google plus pages? You can use Hootsuite to post blogs through RSS feeds to your Google plus pages. First, register
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How to get the directory path and file name from a absolute path in Bash on Linux?
Posted onHow to get the directory path and file name from a absolute path in Bash on Linux? For example, with “/foo/bar/baz.txt”, it will produce: “/foo/bar/” and “baz.txt”. You also have the basename and dirname commands besides of the basename and dirname C API in Linux: [zma@laptop:~]$ p=”/foo/bar/baz.txt” [zma@laptop:~]$ dirname $p /foo/bar [zma@laptop:~]$ basename $p baz.txt
Decrypting a Password Protected RSA Private Key
Posted onI got a password protected RSA private key with headers like (I have the password): —–BEGIN RSA PRIVATE KEY—– Proc-Type: 4,ENCRYPTED DEK-Info: AES-256-CBC,… How to decrypt a password protected RSA private key? You can use the openssl command to decrypt the key: openssl rsa -in /path/to/encrypted/key -out /paht/to/decrypted/key For example, if you have a encrypted
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How to get a free Web server SSL/TLS certificates for my websites?
Posted onCan I get a non-self-assigned and free Web server SSL/TLS certificates for my https websites? Asking the users to accept the self-assigned SSL certificates for my websites is not very convenient. Please check https://letsencrypt.org/ . PS: StartSSL used to provide 1 year free SSL. But StartCom CA is closed since Jan. 1st, 2018.
What about the master branch for local git configuration in a git repository to make it track remote master branch?
Posted onWhat about the master branch for local git configuration in a git repository to make it track remote master branch? You may append these lines to .git/config in your cloned repository directory: [branch “master”] remote = origin merge = refs/heads/master
How to make Chrome on iPhone (iOS) accept self assigned ssl keys fir websites?
Posted onThis tutorial introduces how to make Chrome accept self assigned ssl keys for websites: https://www.systutorials.com/50204/making-chrome-accept-self-signed-certificates-on-linux/ However, on iPhone, Chrome blocks me from access sites with self assigned keys. How to make Chrome on iPhone also accept the ssl keys? At the time when I wrote this reply, there is no way to add Certificate Authorities
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How to fix “Your profile could not be opened correctly.” on Linux?
Posted onI experience the program on Linux (Fedora 12) that Chrome reports “Your profile could not be opened correctly.” as follows. How to fix it? Restarting Chrome would not help. Removing the ‘Web Data’ directories from all profiles works for me (Making backup first as the commands will remove your files): cd ~/.config/google-chrome find ./ -name
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Good Cinnamon theme for Fedora 21 Linux?
Posted onAny suggestion on good theme configuration for Fedora 21 Linux? My favorite combination of Window borders, Icons, Controls, Mouse Pointer and Desktop is as follows. All packages and themes are from Fedora repository or the Cinnamon repository. Remember to set the cursor theme for QT application like Google Chrome following: https://www.systutorials.com/4068/configuring-mouse-cursor-style-for-qt-applications-in-gnome-mate-desktop/ For this configuration, the
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How to redirect STDOUT of sudo command on Linux and write to file as root?
Posted onA try like the following command failed $ sudo echo “echo hello” > /usr/local/bin/hello with an message bash: /usr/local/bin/hello: Permission denied It seems the writing to the file is executed under the non-root user. How to redirect STDOUT of sudo command on Linux and write the content to the file (/usr/local/bin/hello here) as root? You
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How to force a website to use https by htaccess settings?
Posted onI would like my site to be accessed by https only. How to force a website to use https by htaccess settings by redirecting http requests to the corresponding https ones? You can check the method of redirecting http to https at: https://www.systutorials.com/qa/1033/how-to-redirect-http-to-https-in-apache-with-mod_rewrite If you would like to have a 301 redirect, you can use
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Good open-source and free scanner software for Windows?
Posted onAny suggestions on good open-source and free scanner software for Windows? NAPS2 (Not Another PDF Scanner 2) is my favorite opensource scanner software on Windows: http://naps2.sourceforge.net/ Scan documents to PDF and other file types, as simply as possible. NAPS2 is a document scanning application with a focus on simplicity and ease of use. Scan your
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