A Redis cluster proxy.

Build

Requirements:

• make and cmake
• UNIX-like system with SO_REUSEPORT | SO_REUSEADDR support
• epoll support
• pthread
• C++ compiler & lib with C++11 features, like g++ 4.8 or clang++ 3.2 (NOTE: install clang++ 3.2 on CentOS 6.5 won't compile because clang uses header files from gcc, which is version 4.4 without C++11 support)
• Google Test (for test)

To build, just

make

turn on all debug logs

make MODE=debug

or compile with g艹

make COMPILER=g++

To link libstdc++ statically, use

make STATIC_LINK=1

to run test (just cover message parsing parts)

make runtest

run test with valgrind checking

make runtest CHECK_MEM=1

Run

cerberus CONFIG_FILE [ARGS]

The first argument is path of a configuration file, then optional arguments. Those specifies

• bind / -b : (integer) local port to listen; could also specified
• node / -n : (address) active nodes in a cluster; format should be host1:port1,host2:port2; could also set after cerberus launched, via the SETREMOTES command, see it below
• thread / -t : (integer) number of threads
• read-slave / -r : (optional, default off) set to "yes" to turn on read slave mode. A proxy in read-slave mode won't support writing commands like SET, INCR, PUBLISH, and it would select slave nodes for reading commands if possible. For more information please read here (CN).
• read-slave-filter / -R : (optional, need read-slave set to "yes") if multiple slaves replicating one master, use the one whose host starts with this option value; for example, you have 10.0.0.1:7000 as a master, with 2 slave 10.0.1.1:8000 and 10.0.2.1:9000, and read-slave-filter set to 10.0.1, then 10.0.1.1:8000 is preferred. Note this option is no more than a string matching, so 10.0.1.1 and 10.0.10.1 won't be different on option value 10.0.1
• cluster-require-full-coverage : (optional, default on) set to "no" to turn off full coverage mode, so proxy would keep serving when not all slots covered in a cluster.

The option set via ARGS would override it in the configuration file. For example

cerberus example.conf -t 8

set the program to 8 threads.

Commands in Particular

Restricted Commands Bypass

• MGET : execute multiple GETs
• MSET : execute multiple SETs
• DEL : execute multiple DELs
• RENAME : if source and destination are not in the same slot, execute a GET-SET-DEL sequence without atomicity
• BLPOP / BRPOP : one list limited; might return nil value before timeout See detail (CN)
• EVAL : one key limited; if any key which is not in the same slot with the argument key is in the lua script, a cross slot error would return

Extra Commands

• PROXY / INFO: show proxy information, including threads count, clients counts, commands statistics, and remote redis servers
• KEYSINSLOT slot count: list keys in a specified slot, same as CLUSTER GETKEYSINSLOT slot count
• UPDATESLOTMAP: notify each thread to update slot map after the next operation
• SETREMOTES host port host port ...: reset redis server addresses to arguments, and update slot map after that

Not Implemented

• keys: KEYS, MIGRATE, MOVE, OBJECT, RANDOMKEY, RENAMENX, SCAN, BITOP,
• list: BRPOPLPUSH, RPOPLPUSH,
• set: SINTERSTORE, SDIFFSTORE, SINTER, SMOVE, SUNIONSTORE,
• sorted set: ZINTERSTORE, ZUNIONSTORE,
• pub/sub: PUBSUB, PUNSUBSCRIBE, UNSUBSCRIBE,

others: PFADD, PFCOUNT, PFMERGE, EVALSHA, SCRIPT, WATCH, UNWATCH, EXEC, DISCARD, MULTI, SELECT, QUIT, ECHO, AUTH, CLUSTER, BGREWRITEAOF, BGSAVE, CLIENT, COMMAND, CONFIG, DBSIZE, DEBUG, FLUSHALL, FLUSHDB, LASTSAVE, MONITOR, ROLE, SAVE, SHUTDOWN, SLAVEOF, SLOWLOG, SYNC, TIME,

For more information please read here (CN).