RabbitMQ簡介
RabbitMQ 是由 LShift 提供的一個 Advanced Message Queuing Protocol (AMQP) 的開源實現，由以高性能、健壯以及可伸縮性出名的 Erlang 寫成，因此也是繼承了這些優點。消息中間件主要用於組件之間的解耦，消息的發送者無需知道消息使用者的存在，反之亦然。AMQP的主要特征是面向消息、隊列、路由（包括點對點和發布/訂閱）、可靠性、安全。RabbitMQ支持多種客戶端，如：Python、Ruby、.NET、Java、JMS、C、PHP、ActionScript、XMPP、STOMP等，支持AJAX。用於在分布式系統中存儲轉發消息，在易用性、擴展性、高可用性等方面表現不俗。RabbitMQ解決了應用程序之間的互聯(connect)和規模(scale)的問題，消息發送和接收是隔離,發送方不知道消息最終由誰接收,接收方也不必關心消息是誰步發出的;發送和接收是隔離的,消息本質上就是異步的.這種隔離也就解耦了應用程序之間的依賴。RabbitMQ的角色就是應用程序中間的路由器。
規模(scale),應用程序解除了相互依賴之后從業務層面更容易做擴展,而Erlang的先天優勢讓代碼層面的開發也更容易
安裝erlang，執行命令`yum install -y erlang
出現下面圖片則erlang安裝成功。
下載RabbitMQ 執行命令wget http://www.rabbitmq.com/releases/rabbitmq-server/v3.4.2/rabbitmq-server-3.4.2-1.noarch.rpm
安裝RabbitMQ
執行rpm -ivh rabbitmq-server-3.4.2-1.noarch.rpm命令
第一次安裝的時候出現了錯誤 ，##error: unpacking of archive failed on file /usr/lib/rabbitmq/lib/rabbitmq_server-3.4.2/ebin/dtree.beam;564c8512: cpio: read failed - Bad file descriptor##，截圖如下
看到網上說重試幾次可以，我將原來的rpm文件刪除掉，重新下載安裝成功。
執行rabbitmqctl status命令，得到如下的信息
Status of node rabbit@localhost ...
Error: unable to connect to node rabbit@localhost: nodedown
DIAGNOSTICS
===========
attempted to contact: [rabbit@localhost]
rabbit@localhost:
* connected to epmd (port 4369) on localhost
* epmd reports: node 'rabbit' not running at all
no other nodes on localhost
* suggestion: start the node
current node details:
- node name: 'rabbitmqctl-6310@localhost'
- home dir: /var/lib/rabbitmq
- cookie hash: ybKnLWdtnBMcXHwE5BIbig==
執行/etc/init.d/rabbitmq-server restart命令，rabbitmq-server啟動。
再次執行 rabbitmqctl status命令
Status of node rabbit@localhost ...
[{pid,6475},
{running_applications,[{rabbit,"RabbitMQ","3.4.2"},
{mnesia,"MNESIA CXC 138 12","4.5"},
{os_mon,"CPO CXC 138 46","2.2.7"},
{xmerl,"XML parser","1.2.10"},
{sasl,"SASL CXC 138 11","2.1.10"},
{stdlib,"ERTS CXC 138 10","1.17.5"},
{kernel,"ERTS CXC 138 10","2.14.5"}]},
{os,{unix,linux}},
{erlang_version,"Erlang R14B04 (erts-5.8.5) [source] [64-bit] [rq:1] [async-threads:30] [kernel-poll:true]\n"},
{memory,[{total,27093832},
{connection_readers,0},
{connection_writers,0},
{connection_channels,0},
{connection_other,2648},
{queue_procs,2648},
{queue_slave_procs,0},
{plugins,0},
{other_proc,9081872},
{mnesia,57424},
{mgmt_db,0},
{msg_index,35520},
{other_ets,758616},
{binary,8144},
{code,14503690},
{atom,1352841},
{other_system,1290429}]},
{alarms,[]},
{listeners,[{clustering,25672,"::"},{amqp,5672,"::"}]},
{vm_memory_high_watermark,0.4},
{vm_memory_limit,411407155},
{disk_free_limit,50000000},
{disk_free,12885368832},
{file_descriptors,[{total_limit,924},
{total_used,3},
{sockets_limit,829},
{sockets_used,1}]},
{processes,[{limit,1048576},{used,121}]},
{run_queue,0},
{uptime,104}]
接下來安裝mercurial git,執行yum install -y mercurial git命令
繼續安裝 rabbitmq-public-umbrella
cd /var/lib/rabbitmq && hg clone http://hg.rabbitmq.com/rabbitmq-public-umbrella
cd /var/lib/rabbitmq/rabbitmq-public-umbrella && make co
繼續安裝
cd /var/lib/rabbitmq/rabbitmq-public-umbrella/rabbitmq-management && make
cd /var/lib/rabbitmq/rabbitmq-public-umbrella/ && git clone
https://github.com/rabbitmq/rabbitmq-priority-queue
cd /var/lib/rabbitmq/rabbitmq-public-umbrella/rabbitmq-priority-queue && make
cp /var/lib/rabbitmq/rabbitmq-public-umbrella/rabbitmq-priority-queue/dist/rabbitmq_priority_queue-0.0.0.ez
/usr/lib/rabbitmq/lib/rabbitmq_server-3.4.2/plugins/
rabbitmq-plugins enable --offline rabbitmq_priority_queue
rabbitmq-plugins enable --offline rabbitmq_management
/etc/init.d/rabbitmq-server restart
rabbitmqctl status