pycurl: libcurl link-time ssl backend (nss) is different from compile-time ssl backend (openssl)

 

In CentOS/Fedora : Found issue with yum package.

There was a problem importing one of the Python modules
required to run yum. The error leading to this problem was:

pycurl: libcurl link-time ssl backend (nss) is different from compile-time ssl backend (openssl)

Please install a package which provides this module, or
verify that the module is installed correctly.

It’s possible that the above module doesn’t match the
current version of Python, which is:
2.7.5 (default, Nov 6 2016, 00:28:07)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-11)]

If you cannot solve this problem yourself, please go to
the yum faq at:
http://yum.baseurl.org/wiki/Faq

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Solution: Execute below commands in terminal.

#recompile pycurl

#upgrade pip

•   pip install –upgrade pip

---

# Uninstall current pycurl

• pip uninstall pycurl

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#set PYCURL_SSL_LIBRARY

• export PYCURL_SSL_LIBRARY=nss

---

# recompile and install pycurl

• pip install –compile pycurl

---

# Run YUM package manager

• yum clean all
• yum update

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Hope this post will helps..! Enjoy  🙂

 

 

 

Install memcache in CentOS 7

Memcached is a configurable memory object caching daemon that stores objects in memory to reduce database load in dynamic web applications.
It’s built on top of libevent to grow to any size, and it’s specially designed to minimise swapping and utilise non-blocking I/O wherever possible.

Memcached is high performance in memory cache system that is useful to speed up websites  which used heavy database. Memcached support many programming languages like PHP,Ruby,Python,Perl.

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Install Memcached :

• Clean up yum

         [root@linuxsysad ~]# yum clean all

• Update yum packages

         [root@linuxsysad ~]# yum update

• Install Memcached Package.

         [root@linuxsysad ~]# yum -y install memcached

• Start Memcached service:

        [root@linuxsysad ~]# systemctl start memcached

• configure to start memcached service at boot time.

         [root@linuxsysad ~]# systemctl enable memcached

 

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Configure memcached :

The default configuration file can be found at:

/etc/sysconfig/memcached

When started, Memcached will start on port 11211 by default as per the default configuration file:

PORT=”11211″
USER=”memcached”
MAXCONN=”1024″
CACHESIZE=”64″
OPTIONS=””

CACHESIZE is default set in MB. For example we set CACHESIZE=”64″ means it is 64 MB.

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Install Brave Browser in Ubuntu16+ & Mint 18+

 

[root@linuxsysad ~]#sudo apt install apt-transport-https curl

[root@linuxsysad ~]# curl -s https://brave-browser-apt-release.s3.brave.com/brave-core.asc | sudo apt-key –keyring /etc/apt/trusted.gpg.d/brave-browser-release.gpg add –

[root@linuxsysad ~]#source /etc/os-release

[root@linuxsysad ~]#echo “deb [arch=amd64] https://brave-browser-apt-release.s3.brave.com/ $UBUNTU_CODENAME main” | sudo tee /etc/apt/sources.list.d/brave-browser-release-${UBUNTU_CODENAME}.list

[root@linuxsysad ~]#sudo apt update

[root@linuxsysad ~]#sudo apt install brave-browser

Find Command: Find 0 KB files & Directory | name or extension.

Run Below Command in the current directory to find 0 kb files.

We add ‘f’ option for files.

[root@linuxsysad ~]#  find ./ -type f -empty

__ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __

Run Below Command in the current directory to find 0 kb Directories.

We add ‘d’ option for Directory.

[root@linuxsysad ~]#  find ./ -type d -empty

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Find file by name or extension.

We use . option to find all mp4  files in current directory.

[root@linuxsysad ~]# find . -name “*.mp4”

__ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __

We use /home/linuxsysad/  directory path to find all mp4  files in /home/linuxsysad.

[root@linuxsysad ~]# find /home/linuxsysad -name “*.mp4”

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SSH login without password

[root@linuxsysad ~]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase): PRESS ENTER KEY FOR BLANK PASSWORD
Enter same passphrase again: PRESS ENTER KEY FOR BLANK PASSWORD
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:l0G3/GrujoduLPWr7a/k7vjNcwhuF2ONI/oalNMtYVk root@linuxsysad
The key’s randomart image is:
+—[RSA 2048]—-+
| . . E |
| . o + |
| . * |
| * + |
| S * o oo |
| o..oo* .|
| o.=++ = |
| . =X=o+ .|
| +*&#=+o |
+—-[SHA256]—–+

Firefox dbus-send: command not found

Error:

/usr/bin/firefox: line 255: dbus-send: command not found
Starting a11y dbus service…
Failed to launch bus: Failed to connect to session busprocess 6879: D-Bus library appears to be incorrectly set up; failed to read machine uuid: Failed to open “/var/lib/dbus/machine-id”: No such file or directory
See the manual page for dbus-uuidgen to correct this issue.
D-Bus not built with -rdynamic so unable to print a backtrace
Redirecting call to abort() to mozalloc_abort

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Solutions:

1. Make sure dbuspackage installed or not.

#yum install dbus

Then Run follwoing Command in terminal.

# dbus-uuidgen > /var/lib/dbus/machine-id

 

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Command “python setup.py egg_info” failed with error code 1 in /tmp/pip-build-gw9m1v/pycurl

[Tested in centos 6]

ERROR:

Command “python setup.py egg_info” failed with error code 1 in /tmp/pip-build-gw9m1v/pycurl

——————————————————————————————————————————————–

Solution :

Install below package in centos 6.

yum install libcurl-devel

Compile & Install Python 2.7

Compile & Install Python 2.7

# wget http://python.org/ftp/python/2.7.6/Python-2.7.6.tar.xz

# tar xf Python-2.7.6.tar.xz

# cd Python-2.7.6

# ./configure –prefix=/opt

# make && make altinstall

————————————————————————————————————–

To Make default python 2.7 Environment 
Edit /etc/bashrc and at the end of the file past below line.

# alias python=python2.7

————————————————————————————————————–

To update changes run below command in terminal.

# source /etc/bashrc

————————————————————————————————————–

Failed to add the host to the list of known hosts (/home/linuxsysad/.ssh/known_hosts).

ssh root@10.109.61.119
The authenticity of host ‘10.109.61.119 (10.109.61.119)’ can’t be established.
RSA key fingerprint is 32:d7:ea:8b:7f:ff:dc:a3:db:05:93:b7:38:cc:a2:0d.
Are you sure you want to continue connecting (yes/no)? yes
Failed to add the host to the list of known hosts (/home/linuxsysad/.ssh/known_hosts).

________________________________________________________________

It happened to me simply because of broken permissions. My user did not have read nor write access to that file. Fixing permissions fixed the problem.

Run Following command

chmod u+w ~/.ssh/known_host

OR

sudo chown -v $USER ~/.ssh/known_hosts

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