Why I cannot login remote server with its root

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# ssh root@192.168.122.96 root@192.168.122.96’s password: Permission denied, please try again. Do according to [1]. NOTE: on Ubuntu, remember to restart ssh service like this “sudo restart ssh”. [1] https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/v2v_guide/preparation_before_the_p2v_migration-enable_root_login_over_ssh

In Python, `os.makedirs()` with 0777 mode does not give others write permission

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In Python, os.makedirs() with 0777 mode can not give others write permission The code is as follows $ python Python 2.7.5 (default, Aug 4 2017, 00:39:18) [GCC 4.8.5 20150623 (Red Hat 4.8.5-16)] on linux2 Type “help”, “copyright”, “credits” or “license” for more information. >>> import os >>> os.makedirs(“/tmp/test1/test2”, 0777) >>> The created dirs are not
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Cannot make directory ‘/var/run/screen/S-apache’: Permission denied

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Hello! Im trying to create a screen folder for the user apache, Not root. But it seems to fail, I have no idea on how to fix this issue. I only get the error: Cannot make directory ‘/var/run/screen/S-apache’: Permission denied Im using Cent OS 7 There may be various possible reasons. 2 common reasons: screen
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encfs on CentOS 6 can’t mount as normal user

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On CentOS 7, using a normal user, encfs works just well. On CentOS 6, using the root user, encfs works. However, the problem is, on CentOS 6, using a normal user account, encfs does not work as on CentOS 7. $ encfs -s ~/t/.enc ~/t/enc EncFS Password: fuse: failed to exec fusermount: Permission denied fuse
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Allowing root Access to NFS Directories

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For local filesystems, root usually has full access (read/write) to directories/files inside of it. But for NFS directory mounted from network, root usually has no permission to write to directories or files within the NFS directory. How to make root act similarly in an NFS directory to the behavior in local directories? The reason that
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Linux boots failed with “sulogin: can not open password database” while the /etc/passwd and /etc/shadow files look fine

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Linux boots failed with “sulogin: can not open password database” while the /etc/passwd and /etc/shadow files look fine. How to fix this? The OS is Fedora 22. You may try this trick Step 1: boot Linux with rw init=/bin/bash following this tutorial. Step 2: after Linux booted, disable SELinux following this tutorial. Reboot. If it
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How to run screen on a Linux host reporting “Cannot make directory ‘/var/run/screen’: Permission denied”?

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I want to run screen on a remote host on which I do not have root/sudo privilege and screen is not installed. I can compile or copy the screen program that can run on the host. However, it reports: “Cannot make directory ‘/var/run/screen’: Permission denied” As screen is not installed on the host, the directory
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How to redirect STDOUT of sudo command on Linux and write to file as root?

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A 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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Bash comparison operators

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What are all the bash supported comparison operators? The man 1 test contains all the operators supported in bash. An omitted EXPRESSION defaults to false. Otherwise, EXPRESSION is true or false and sets exit status. It is one of: ( EXPRESSION ) EXPRESSION is true ! EXPRESSION EXPRESSION is false EXPRESSION1 -a EXPRESSION2 both EXPRESSION1
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How to Change the DPI of Images Exported from Slides in PowerPoint

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PowerPoint uses 96 dots per inch (dpi) by default when you export a slide. The DPI of the images like .tif ones exported from PowerPoint are always 96. In the options of PowerPoint, there is a setting for choosing DPIs. However, it have no effect. For some needs like images for printing posters, larger DPIs
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Unified Linux Login and Home Directory Using OpenLDAP and NFS/automount

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In this post, how to unified Linux login and home directory using OpenLDAP and NFS/automount will be introduced. 0. System environment This solution is tested on Fedora 12 systems and CentOS 5. LDAP and NFS server: IP: 10.0.0.2 OS: Fedora 12 x86_64 ldap base dn: “dc=lgcpu1″ Clients: IP: 10.0.0.1/24 OS: Fedora 12 x86_64 1. LDAP
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How to Set Up and Configure NFS Server and Clients

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NFS is widely deployed and used even after more than twenty year. NFS is easy to set up and easy to use. This introduces how to set up the NFS server and clients. We use the Fedora system as the example. The tutorial here is for RHEL/CentOS/Fedora and derived Linux OSes. Set up an NFS
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How to Get System Uptime on Linux and Windows OSes

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How to find out Linux and Windows uptime is introduced in this post. Linux uptime Linux uptime can be easily found out by the uptime command: $ uptime 22:19:29 up 10 days, 22:26,  5 users,  load average: 0.00, 0.00, 0.00 The system is up for 10 days, 22 hours and 26 minutes. uptime gives a
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NVIDIA Driver in Linux not Displaying Logo During Booting

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The NVIDIA video card driver in Linux will display the NVIDIA logo by default during booting the X server after we successfully installed the driver. If we don’t like to see the logo every time we start X server, we can disable it. We need to edit the Xorg configuration file /etc/X11/xorg.conf with root permission.
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How to Backup Linux Home Directories Using rsync

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I need to backup my Linux home directory to one of my portable hard disk. I tried to use git, but failed since git doesn’t support large file (I failed after many tries, I have file larger than 5G). I find rsync, the fast, versatile, remote (and local) file-copying tool and I am happy with
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How to Set Up Password-less SSH Login on Linux

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Automatic passwrod-less ssh login can make our life easier. To enable this, we have 2 options: using key-based authentication by copying our SSH public keys to the remote machines for automatic password-less login or using password-based authentication. I will introduce the 2 options in the post. Before you start, please note that key-based authentication is
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Howto: Git Server over SSH

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Git and SSH are both powerful tools, and git/ssh work well together. We introduce how to set up git server via ssh in this post. Git server through SSH is easy and fast to set up, although every user will have access to all repositories in the git server over SSH and every user is
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ld-linux.so Taking High CPU Usage Caused by Adobe Reader

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解决ld-linux.so大量占用CPU 注: 这是在低版本上的Adobe Reader导致的, 较新版本可能已经无此问题. — Zhiqiang Ma on Oct. 29, 2011 在我这边是因为adobe reader导致的. 我解决的方法是这样子的: 1. 复制一份libgtkembedmoz.so并认reader使用它, 这个在preferrence中找到设置一下就可以了, 我是从thunderbird中找到的. 2. #setsebool -P allow_execheap=1 关于这个的相关解释如下 ************************************************************* The following error pops up in setroubleshooter when opening a PDF form with Adobe Reader 8.1.2 on a Fedora 8 system with SELinux in enforcing mode. It looks like an
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