Linux

First simulate grub corruption, DD If=/dev/zero OF=/DEV/SDA count=1 bs=400Grub boot corruption, but does not restart at this time, you can reinstall grub directly to restore GRUB:The first method: 1. First enter grub into GRUB command line[[email

for DHCP services, settings can be made on many platforms. So here we will focus on the Linux DHCP server via option 43 implementation of the H3C AP automatically contact the relevant content of the AC registration. The original DHCP server was

Run Elasticsearch 2.3 on CentOS 6.5 with the following exceptions:ExceptioninchThread"Main"Java.lang.RuntimeException:don ' tRunElasticsearch asRoot. atOrg.elasticsearch.bootstrap.Bootstrap.initializeNatives (Bootstrap.java: the) atOrg.elasticsearch.

I. File locationLocation in general under the/var/spool/cron/, if you are the root user, then there is a root file, recommended daily backup, to avoid accidental deletion resulting in crontab file loss;Two. log file locationBy default, the logs

LN is another very important command in Linux, and its function is to create a synchronized link for a file in another location, broken down into soft links and hard links. Soft links are equivalent to Windows shortcuts, and here are the ways to use

Here are some of the Linux commands to organize, there are: Sleep, suspend, standby, shutdown and other commands of the difference and how to achieve.hibernation is a more power-saving mode that saves in-memory data to the hard disk and all devices

Content:1. FTP protocol2, the construction and configuration of VSFTPDFirst, the FTP protocol1. FTP protocol:FTP is the abbreviation for file Transfer Protocol (document Transfer Protocol), and Chinese is called "Interfax protocol". Works on the

Guide A benchmark is a test or a series of tests to determine how well a computer's hardware is running. In many cases, a "benchmark" is actually equivalent to a "stress test." By testing the limits of the hardware, you can then compare the

The meaning of permissions (R, W, x) in Linux for directories and filesFirst, the significance of the permissions for the directory1, the first thing to understand is that the main content of the directory is to record the list of file names and sub-

1 command line Input directly: Iptraf (if not, install with yum install Iptraf)2. Open Enter to select IP image.3. Select the interface for the monitoring test, all interfaces.4. Turn on the listening status log and the system default log path. /var/

If your Linux server suddenly has a sudden increase in load, alarm text messages quickly explode your phone, how to find out the Linux performance problem in the shortest time? Look at the Netflix performance Engineering team's blog post to diagnose

1./proc DirectoryThe Linux kernel provides a mechanism for accessing kernel internal data structures and changing kernel settings at run time through the/proc file system. The proc file system is a pseudo-file system that only exists in memory and

(1) Su and sudoSU: Can be switched between users through Su, what is power if superuser root switches to normal or virtual users without a password? That's it! And the normal user to switch to any other users need password authentication;Sudo:Sudo's

Problem Description:Today after work, log in an intranet test server, found that some of the process is missing (Nginx/php-fpm/mysql/crond).Workaround:1, start these processes first, to ensure the normal provision of services.2, check the server log

OutlineDefinition of a highly available clusterIi. metrics for high-availability clustersIII. hierarchical structure of highly available clustersIv. classification of high-availability clustersFive, high-availability cluster common softwareVi.

ArrayWhat is an array?An array in a computer refers to a data type that is organized in a certain order by a number of variables of the same type .The popular point is that the array is one of the variables, in terms of the current term is a

HAProxy introduction, haproxySimple Description HAProxy provides high availability, Server Load balancer, and TCP and HTTP application-based proxy. It supports Virtual Hosts and is a free, fast, and reliable solution. HAProxy is especially suitable

Linux File Permission, linux permissionPermission deny Permission drop view Permission ls-a ls-la expression view Permission of the folder Classification group of user groups: an operating system may be used by several people to facilitate the

In CentOS 7, how does one set the DNS server and centosdns?In CentOS 7, manually set the DNS in/etc/resolv. conf. After a while, the system will overwrite or clear the DNS. Different from setting DNS in CentOS 6, there are several methods: 1. Use

Docker + swarm ClusterDocker + swarm ClusterGuideSwarm is a new container management tool released by Docker in early December 2014. Docker management tools released with Swarm include Machine and Compose. Swarm is a simple tool used to manage