月度归档:2015年12月

Centralized Secure Storage (iSCSI) – “Initiator Client” Setup on RHEL/CentOS/Fedora – Part III

iSCSI Initiator are the clients which use to authenticated with iSCSI target servers to access the LUNs shared from target server. We can deploy any kind of Operating systems in those locally mounted Disks, just a single package need to be install to get authenticate with target server.

Client Initiator Setup

Client Initiator Setup

Features

  1. Can handle any kind of file systems in locally mounted Disk.
  2. No need of restating the system after partition using fdisk.

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How to Create and Setup LUNs using LVM in “iSCSI Target Server” on RHEL/CentOS/Fedora – Part II

LUN is a Logical Unit Number, which shared from the iSCSI Storage Server. The Physical drive of iSCSI target server shares its drive to initiator over TCP/IP network. A Collection of drives called LUNs to form a large storage as SAN (Storage Area Network). In real environment LUNs are defined in LVM, if so it can be expandable as per space requirements.

Create LUNS using LVM in Target Server

Create LUNS using LVM in Target Server

Why LUNS are Used?

LUNS used for storage purpose, SAN Storage’s are build with mostly Groups of LUNS to become a pool, LUNs are Chunks of a Physical disk from target server. We can use LUNS as our systems Physical Disk to install Operating systems, LUNS are used in Clusters, Virtual servers, SAN etc. The main purpose of Using LUNS in Virtual servers for OS storage purpose. LUNS performance and reliability will be according to which kind of disk we using while creating a Target storage server. 继续阅读

Create Centralized Secure Storage using iSCSI Target on RHEL/CentOS/Fedora Part -I

iSCSI is a block level Protocol for sharing RAW Storage Devices over TCP/IP Networks, Sharing and accessing Storage over iSCSI, can be used with existing IP and Ethernet networks such as NICs, Switched, Routers etc. iSCSI target is a remote hard disk presented from an remote iSCSI server (or) target.

Install iSCSI Target in Linux

Install iSCSI Target in Linux

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CentOS / Red Hat Linux: Install and manage iSCSI Volume

Internet SCSI (iSCSI) is a network protocol s that allows you to use of the SCSI protocol over TCP/IP networks. It is good alternative to Fibre Channel-based SANs. You can easily manage, mount and format iSCSI Volume under Linux. It allows access to SAN storage over Ethernet.

Open-iSCSI Project

Open-iSCSI project is a high-performance, transport independent, multi-platform implementation of iSCSI. Open-iSCSI is partitioned into user and kernel parts.

Instructions are tested on:
[a] RHEL 5
[b] CentOS 5
Fedora 7
[d] Debian / Ubuntu Linux 继续阅读

Strong SSL Security on Apache2

ssl-labs-2This tutorial shows you how to set up strong SSL security on the Apache2 webserver. We do this by updating OpenSSL to the latest version to mitigate attacks like Heartbleed, disabling SSL Compression and EXPORT ciphers to mitigate attacks like FREAK, CRIME and LogJAM, disabling SSLv3 and below because of vulnerabilities in the protocol and we will set up a strong ciphersuite that enables Forward Secrecy when possible. We also enable HSTS and HPKP. This way we have a strong and future proof ssl configuration and we get an A+ on the Qually Labs SSL Test. 继续阅读

haproxy配置范例

HaProxy特性

HAProxy提供高可用性、负载均衡以及基于TCP和HTTP应用的代理,支持虚拟主机,它是免费、快速并且可靠的一种解决方案。根据官方数据,其最高极限支持10G的并发。

HAProxy特别适用于那些负载特大的web站点,这些站点通常又需要会话保持或七层处理。HAProxy运行在当前的硬件上,完全可以支持数以万计的并发连接。并且它的运行模式使得它可以很简单安全的整合进您当前的架构中,同时可以保护你的web服务器不被暴露到网络上。

其支持从4层至7层的网络交换,即覆盖所有的TCP协议。就是说,Haproxy 甚至还支持 Mysql 的均衡负载(read)。

如果说在功能上,能以proxy反向代理方式实现WEB均衡负载,这样的产品有很多。包括 Nginx,ApacheProxy,lighttpd,Cheroke 等。

但要明确一点的,Haproxy 并不是 Http 服务器。以上提到所有带反向代理均衡负载的产品,都清一色是 WEB 服务器。简单说,就是他们能自个儿提供静态(html,jpg,gif..)或动态(php,cgi..)文件的传输以及处理。而Haproxy 仅仅,而且专门是一款的用于均衡负载的应用代理。其自身并不能提供http服务。

但其配置简单,拥有非常不错的服务器健康检查功能还有专门的系统状态监控页面,当其代理的后端服务器出现故障, HAProxy会自动将该服务器摘除,故障恢复后再自动将该服务器加入。自1.3版本开始还引入了frontend、backend,frontend根据任意HTTP请求头内容做规则匹配,然后把请求定向到相关的backend。 继续阅读

Windows Server 2012 R2 同一用户多会话登陆策略设置

1、Win+R,输入:Gpedit.msc,回车;
2、打开”计算机配置” > “管理模板” > “Windows组件” > “远程桌面服务” > “远程桌面会话主机” > “连接”;
3、禁用”将远程桌面服务用户限制到单独的远程桌面服务会话”;启用”限制连接的数量”,填入同时连接的数量。

不同场景下 MySQL 的迁移方案

一 目录


二 为什么要迁移

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