MongoDB(AutoSharding+Replication sets 稳定性测试 )

单Replication sets设计：

如图所示,10.9.3.228只启动Mongos和config两个服务

^_^[root@:/usr/local/mongodb/bin]#cat runServerConfig.sh 
./mongod --configsvr --dbpath=../data/config --logpath=../data/config.log --fork 
^_^[root@:/usr/local/mongodb/bin]#cat runServerMongos.sh 
./mongos --configdb 10.7.3.228:27019 --logpath=../data/mongos.log --logappend --fork

注意：Mongos里面的ip和端口是config服务的ip和端口

先进性配置AutoSharding

163的shardv已经启动了，只要启动下165服务器的autoSharding服务

[root@localhost bin]# cat runServerShard.sh 
./mongod --shardsvr -dbpath=../data/mongodb --logpath=../data/shardsvr_logs.txt --fork

配置163和164的Replication

[root@localhost bin]# ./mongo 10.10.21.163:27018
MongoDB shell version: 1.8.2
connecting to: 10.10.21.163:27018/test
> cfg={_id:"set163164",members:[                            
... {_id:0,host:"10.10.21.163:27018"},
... {_id:1,host:"10.10.21.164:27017"}
... ]}
{
        "_id" : "set163164",
        "members" : [
                {
                        "_id" : 0,
                        "host" : "10.10.21.163:27018"
                },
                {
                        "_id" : 1,
                        "host" : "10.10.21.164:27017"
                }
        ]
}
> rs.initiate(cfg)
{
        "info" : "Config now saved locally.  Should come online in about a minute.",
        "ok" : 1
}
> rs.conf()
{
        "_id" : "set163164",
        "version" : 1,
        "members" : [
                {
                        "_id" : 0,
                        "host" : "10.10.21.163:27018"
                },
                {
                        "_id" : 1,
                        "host" : "10.10.21.164:27017"
                }
        ]
}
set163164:PRIMARY> 
set163164:PRIMARY> 
set163164:PRIMARY> show dbs
admin   (empty)
local   14.1962890625GB
set163164:PRIMARY> use local
switched to db local
set163164:PRIMARY> show collections
oplog.rs
system.replset
set163164:PRIMARY> db.system.replset.find()
{ "_id" : "set163164", "version" : 1, "members" : [
        {
                "_id" : 0,
                "host" : "10.10.21.163:27018"
        },
        {
                "_id" : 1,
                "host" : "10.10.21.164:27017"
        }
] }
set163164:PRIMARY> rs.isMaster()
{
        "setName" : "set163164",
        "ismaster" : true,
        "secondary" : false,
        "hosts" : [
                "10.10.21.163:27018",
                "10.10.21.164:27017"
        ],
        "maxBsonObjectSize" : 16777216,
        "ok" : 1
}

至此Replication sets配置成功！

再在228服务器上进行相应Sharding配置

use admin

> db.runCommand({addshard:"set163164/10.10.21.163:27018,10.10.21.165:27018"}); 
{ "shardAdded" : "set163164", "ok" : 1 }
> db.runCommand({enableSharding:"test"})  
{ "ok" : 1 }

> db.runCommand({shardcollection:"test.users",key:{_id:1}})  
{ "collectionsharded" : "test.users", "ok" : 1 }

然后分别在163和164服务器上启动rep服务，163要单独启动shard服务

163:

[root@localhost bin]# cat runServerShard.sh 
./mongod --shardsvr --dbpath=../data/mongodb --logpath=../data/shardsvr_logs.txt --fork --replSet set163164

164:

[root@localhost bin]# cat runServerShard.sh 
./mongod --dbpath=../data --logpath=../data/shardsvr_logs.txt --fork --replSet set163164 

至此AutoSharding+Rep配置成功。然后进行测试稳定性阶段。

先看下结果：

可以看到，总共插入2000W条数据，163和164相同大小 165属于分片 数据。

我现在进行稳定性测试:

断掉163服务器。

Mongos那再相应进行查询：

> db.users.find()
error: { "$err" : "error querying server: 10.10.21.163:27018", "code" : 13633 }
> db.users.find()
error: {
        "$err" : "DBClientBase::findOne: transport error: 10.10.21.163:27018 query: { setShardVersion: \"test.users\", configdb: \"10.7.3.228:27019\", version: Timestamp 11000|1, serverID: ObjectId('4e2f64af98dd90fed26585a4'), shard: \"shard0000\", shardHost: \"10.10.21.163:27018\" }",
        "code" : 10276
}
> db.users.find()                                                                           
error: { "$err" : "socket exception", "code" : 11002 }

直接出现错误！

再进行手动添加164服务器！

> db.runCommand({addshard:"10.10.21.164:27017"}); 
{
        "ok" : 0,
        "errmsg" : "host is part of set: set163164 use replica set url format <setname>/<server1>,<server2>,...."
}

还是出错！

可见这样配置是有问题的！

经过一段时间的思考和反复测试，发现是否是投票上除了问题

看到官网上有这样一段话：

Consensus Vote

For a node to be elected primary, it must receive amajorityof votes. This is a majority of all votes in the set: if you have a 5-member set and 4 members are down, a majority of the set is still 3 members (floor(5/2)+1). Each member of the set receives a single vote and knows the total number of available votes.

If no node can reach a majority, then no primary can be elected and no data can be written to that replica set (although reads to secondaries are still possible).

那么2台Server投票是否会出现问题，那再加一台如何？

这边也可以 把164作为 arbiter来 ：

use admin
var cfg={_id:"set162163164", members:[{_id:0,host:"10.10.21.162:27018"}, {_id:1,host:"10.10.21.163:27017"}, {_id:2,host:"10.10.21.164:27017",arbiterOnly:true} ]}
rs.initiate(cfg)
rs.conf()

228：

use admin
#db.runCommand({addshard:"set162163164/10.10.21.162:27018,10.10.21.163:27017,10.10.21.164:27017"})       #正常添加3台
db.runCommand({addshard:"set162163164/10.10.21.162:27018,10.10.21.163:27017"})       #arbiter
db.runCommand({addshard:"10.10.21.165:27018"}) 
db.runCommand({enableSharding:"test"}) 
db.runCommand({shardcollection:"test.users",key:{_id:1}})

经过试验：

稳定性已经提高，断掉162，163，164任意一台Server ，Mongos都能自动reconnect中其中的vote的一个成员primary.

最终设计图：