webpass availability

the data inconsistency between the main library and the library.The backend database still requires clustering, but coherence reduces the pressure on the backend database, the cluster can be simple, the nodes can be reduced.In terms of sharding, the coherence has built-in distributed queries and aggregations features. Make multi-node queries simple, applications don't need to make too many changes, and data is protected by replication.Coherence and scalabilityCoherence is the ideal scalable dat

1. OverviewWhen we consider the highly available architecture of the MySQL database, we mainly consider the following aspects:1.1 If the database is down or an unexpected outage, and so on, can restore the availability of the database as soon as possible to reduce downtime, to ensure that the business will not be interrupted due to database failure.1.2 Data for non-primary nodes that are used as backups, read replicas, and so on, should be in real-tim

The concept of cluster and high availability (HA), clusterha Reposted from: http://www.cnblogs.com/blackwizard2016/p/5143816.html, which is used only for learning. 1.1 What isCluster To put it simply,Cluster (ClusterIs a group of computers,They provide users with a set of network resources as a whole. TheseA single computer system is a cluster node ). An ideal cluster is that the user will never realize the underlying node of the cluster system. In hi

Mysql master-slave replication and lvs43; keepalived achieves load high availability directory 1. preface 42. principle 421. Overview 422. Working principle 423. actual action 43. solution 431. environment 43. mysql master-slave replication and lvs + keepalived achieve load high available Directory 1. Preface 4 2. Principle 4 2.1 Overview 4 2.2 Working Principle 4 2.3. actual purpose 4 3 Solution 4 3.1. Environment 4 3.2 Architecture 5 3.3 Design

High Availability is divided into three layers: 1. Implementation of the underlying information layer:HeartbeatCorosyncCman2. Resource Management, implementation method:Heartbeat-V1: haresourceHeartbeat-V2: crmHeartbeat-V3: pacemakerRHCS: rgmanagerNote: Resource Manager pacemaker can be used in combination with all underlying communication implementation methods.3. Resource proxy layer, implementation method:Heartbeat-v1LSBOCFSTONITH To achieve high

Configure the NTP server and Heartbeat V1 for httpd High Availability Establishment and use of NTP servers In high-availability clusters, the time requirements for each node are strict. Therefore, we need to configure an NTP server to implement the time synchronization of highly available clusters. Point other node time to this ntp and create an NTP server first. [Root @ localhost ~ ] # Rpm-q ntpNtp-4.2.6p5

, add two back-end databases MBX the server and give Full Control permissions650) this.width=650; "title=" image "style=" border-top:0px;border-right:0px;background-image:none;border-bottom:0 px;padding-top:0px;padding-left:0px;margin:0px;border-left:0px;padding-right:0px; "border=" 0 "alt=" image "src=" Http://s3.51cto.com/wyfs02/M02/5B/61/wKiom1UHkHijTP4GAAHDpwSNaiU963.jpg "height=" 484 "/>23. Create a DAG availability GroupIn the ECP console, selec

Small Q: All things must be seen farther, farther, when you take the first step, the heart must be a third step,The second step can be your chips, no chips of life,Destined to live in the palm of others.Today I learned a very good knowledge, I found that my recent slow progress, extenuating, all day just to see two or three knowledge points, but every knowledge point I will study for a long time, although I know I will forget, butPerhaps I review again, the principle I will not forget, the purpo

This chapter describes how to add a Lync server to the Lync Server front End PoolLync Server front-end high-availability implementation method Three, in fact, the Microsoft Official website method only lists two, and many articles on the network emphasize the inability to use the Windows-based Network Load balancing for high-availability configuration DNS polling, which can be used to distribute ne

MySQL High-availability components MHA parameters MHA is currently a relatively mature solution for MySQL high availability, developed by the Japanese, and is an excellent set of highly available software for failover and master-slave upgrading in MySQL high-availability environments. MHA provides a series of configuration parameters, in-depth understanding of th

HDFS FederationNamenode saves the reference relationship for each file in the file system and each block of data in memory, which means that for an oversized cluster with a large number of files, memory becomes the bottleneck that limits the scale of the system. The Federation HDFS introduced in the 2.0 release series allowsThe system is extended by adding namenode, where each namenode manages a portion of the file system's namespace. In the Federation environment, each Namenode maintains a name

16.4 Monitoring AlwaysOn availability Groups16.4.1 Open the Display panelIn SSMS, select an availability group, right-click it, and then select Display Panel from the context menu.650) this.width=650; "src=" Http://s3.51cto.com/wyfs02/M00/6E/6B/wKiom1V7wXPC1zf8AAO2-VOsZqo757.jpg "title=" Display panel. png "alt=" wkiom1v7wxpc1zf8aao2-voszqo757.jpg "/>The information displayed on the panel is divided into 3

Keepalived for High AvailabilityKeepalived for High Availability Reference: 1. keepaliveduser guide: http://www.keepalived.org/pdf/UserGuide.pdf 2. Installation documentation: INSTALL documentation in the source code extraction package This article involves keepalived installation, simple configuration, and high availability for haproxy.I. Environment preparation 1. Operating System CentOS-7-x86_64-Everyth

Typically, enterprise-class applications use more expensive hardware and software devices to improve system availability.such as IBM's minicomputer and even midsize machine mainframe and proprietary operating system, Oracle database, EMC storage devices and so on.Internet companies are increasingly using PC-class servers, open-source databases, and operating systems, and these inexpensive devices reduce availability while saving costs.In particular, t