Twemproxy是Twitter開源的Redis代理，藉助其可實現穩定的Redis分佈式方案，相對於官方較新的Redis Cluster架構，容量伸縮較麻煩。
安裝比較簡單，注意可能會遇到autoconf版本低的問題。
安裝依賴庫
# yum install autoconf libtool -y
下載最新版本
https://github.com/twitter/twemproxy/releases
編譯安裝twemproxy
# tar zxf twemproxy-0.4.1.tar.gz
# cd twemproxy-0.4.1
遇到autoconf版本低的報錯
# autoreconf -fvi
...
configure.ac:8: error: Autoconf version 2.64 or higher is required
下載較高版本的autoconf
http://ftp.gnu.org/gnu/autoconf/autoconf-2.69.tar.gz
編譯安裝autoconf，並覆蓋低版本文件
# ./configure
# make
# make install
# cp /usr/local/bin/autoconf /usr/bin/
# cp /usr/local/bin/autoreconf /usr/bin/
重新安裝
# autoreconf -fvi
# ./configure --prefix=/usr/local/twemproxy
# make
# make install
twemproxy的重要特性
1. Maintains persistent server connections.
2. Keeps connection count on the backend caching servers low.
3. Enables pipelining of requests and responses.
4. Supports multiple server pools simultaneously.
5. Observability via stats exposed on the stats monitoring port.
6. Supports multiple hashing modes including consistent hashing and distribution.
配置文件，其中端口6379和6389爲2個Redis實例。
$ cat kp.conf
kp:
listen: 127.0.0.1:7379
hash: fnv1a_64
distribution: ketama
timeout: 100
auto_eject_hosts: true
server_retry_timeout: 2000
server_failure_limit: 2
redis: true
redis_auth: abcdefg
servers:
- 127.0.0.1:6379:1
- 127.0.0.1:6389:1
啓動twemproxy
$ nutcracker --daemonize --verbose=11 --output=nut.log --conf-file=kp.conf --stats-port=22222 --pid-file=nut.pid
登陸twemproxy
$ redis-cli -p 7379 -a abcdefg
127.0.0.1:7379> get hello
"redis"
127.0.0.1:7379> set twe proxy
OK
127.0.0.1:7379> dbsize
Error: Server closed the connection
獲取twemproxy狀態
$ curl --get http://127.0.0.1:22222
{"service":"nutcracker", "source":"51", "version":"0.4.1", "uptime":22766,
...
}
若感興趣可關注訂閱號”數據庫最佳實踐”(DBBestPractice).
