4

MongoDB主备仲裁节点关闭顺序

 3 years ago
source link: https://www.wencst.com/archives/1809
Go to the source link to view the article. You can view the picture content, updated content and better typesetting reading experience. If the link is broken, please click the button below to view the snapshot at that time.

MongoDB主备仲裁节点关闭顺序

作者: wencst 分类: linux,架构设计 发布时间: 2019-07-17 13:03 阅读： 3,523 次

MongoDB分为三个角色节点：Primary（P）、Secondary（S）、Arbiter（A），但是关闭顺序不正确，关闭时就会有问题，有些时候，关闭后启动也会有问题。

因此需要有一个正确的顺序来关闭MongoDB集群。下方为实验顺序：

1：关闭顺序PSA ：会报错
2：关闭顺序PAS ：可以
3：关闭顺序SAP ：主节点会变为从节点
4：关闭顺序SPA ：会报错
5：关闭顺序APS
6：关闭顺序ASP ：主节点会变为从节点

服务查看：

gechongrepl:PRIMARY> rs.isMaster()
{
    "setName" : "gechongrepl",
    "setVersion" : 13,
    "ismaster" : true,
    "secondary" : false,
    "hosts" : [
        "192.168.91.133:27017",
        "192.168.91.132:27017",
        "192.168.91.132:27018"
    ],
    "arbiters" : [
        "192.168.91.135:27017"
    ],
    "primary" : "192.168.91.133:27017",
    "me" : "192.168.91.133:27017",
    "electionId" : ObjectId("5568098a6de3d53a2ea91c64"),
    "maxBsonObjectSize" : 16777216,
    "maxMessageSizeBytes" : 48000000,
    "maxWriteBatchSize" : 1000,
    "localTime" : ISODate("2015-05-29T06:39:36.548Z"),
    "maxWireVersion" : 3,
    "minWireVersion" : 0,
    "ok" : 1
}

1：关闭顺序PSA

gechongrepl:PRIMARY> use admin
switched to db admin
gechongrepl:PRIMARY> db.shutdownServer()
从变为了：gechongrepl:PRIMARY>
<br><br>gechongrepl:PRIMARY> use admin
switched to db admin
gechongrepl:PRIMARY> db.shutdownServer()
assert failed : unexpected error: Error: shutdownServer failed: No electable secondaries caught up as of 2015-05-28T23:48:06.022-0700
Error: assert failed : unexpected error: Error: shutdownServer failed: No electable secondaries caught up as of 2015-05-28T23:48:06.022-0700
at Error (<anonymous>)
at doassert (src/mongo/shell/assert.js:11:14)
at assert (src/mongo/shell/assert.js:20:5)
at DB.shutdownServer (src/mongo/shell/db.js:212:9)
at (shell):1:4
2015-05-28T23:48:06.023-0700 E QUERY Error: assert failed : unexpected error: Error: shutdownServer failed: No electable secondaries caught up as of 2015-05-28T23:48:06.022-0700
at Error (<anonymous>)
at doassert (src/mongo/shell/assert.js:11:14)
at assert (src/mongo/shell/assert.js:20:5)
at DB.shutdownServer (src/mongo/shell/db.js:212:9)
at (shell):1:4 at src/mongo/shell/assert.js:13
gechongrepl:ARBITER> use admin
switched to db admin
gechongrepl:ARBITER> db.shutdownServer()

再关闭S：

S变为了：ggechongrepl:SECONDARY>
 
gechongrepl:SECONDARY> use admin
switched to db admin
gechongrepl:SECONDARY> db.shutdownServer()

2：关闭顺序PAS : 已经验证，不报错。

3：关闭顺序SAP

gechongrepl:SECONDARY> use admin
switched to db admin
gechongrepl:SECONDARY> db.shutdownServer()
gechongrepl:ARBITER> use admin
switched to db admin
gechongrepl:ARBITER> db.shutdownServer()
主变为了：gechongrepl:SECONDARY>
 
gechongrepl:SECONDARY> use admin
switched to db admin
gechongrepl:SECONDARY> db.shutdownServer()

4：关闭顺序SPA

gechongrepl:SECONDARY> use admin
switched to db admin
gechongrepl:SECONDARY> db.shutdownServer()
gechongrepl:PRIMARY> use admin
switched to db admin
gechongrepl:PRIMARY> db.shutdownServer()
assert failed : unexpected error: Error: shutdownServer failed: No electable secondaries caught up as of 2015-05-28T23:59:19.685-0700
Error: assert failed : unexpected error: Error: shutdownServer failed: No electable secondaries caught up as of 2015-05-28T23:59:19.685-0700
    at Error (<anonymous>)
    at doassert (src/mongo/shell/assert.js:11:14)
    at assert (src/mongo/shell/assert.js:20:5)
    at DB.shutdownServer (src/mongo/shell/db.js:212:9)
    at (shell):1:4
2015-05-28T23:59:19.702-0700 E QUERY    Error: assert failed : unexpected error: Error: shutdownServer failed: No electable secondaries caught up as of 2015-05-28T23:59:19.685-0700
    at Error (<anonymous>)
    at doassert (src/mongo/shell/assert.js:11:14)
    at assert (src/mongo/shell/assert.js:20:5)
    at DB.shutdownServer (src/mongo/shell/db.js:212:9)
    at (shell):1:4 at src/mongo/shell/assert.js:13
gechongrepl:ARBITER> use admin
switched to db admin
gechongrepl:ARBITER> db.shutdownServer()

再次关闭P：

gechongrepl:PRIMARY> use admin
switched to db admin
2015-05-29T00:00:44.938-0700 I NETWORK  DBClientCursor::init call() failed
2015-05-29T00:00:44.940-0700 I NETWORK  trying reconnect to 127.0.0.1:27017 (127.0.0.1) failed
2015-05-29T00:00:44.941-0700 I NETWORK  reconnect 127.0.0.1:27017 (127.0.0.1) ok
gechongrepl:SECONDARY> db.shutdownServer()

5：关闭顺序APS

gechongrepl:ARBITER> use admin
switched to db admin
gechongrepl:ARBITER> db.shutdownServer()
gechongrepl:PRIMARY> use admin
switched to db admin
gechongrepl:PRIMARY> db.shutdownServer()

S：因为仲裁节点关闭了。所以Primary节点不会再自动切换

gechongrepl:SECONDARY> use admin
switched to db admin
gechongrepl:SECONDARY> db.shutdownServer()

6：关闭顺序ASP

gechongrepl:ARBITER> use admin
switched to db admin
gechongrepl:ARBITER> db.shutdownServer()
gechongrepl:SECONDARY> use admin
switched to db admin
gechongrepl:SECONDARY> db.shutdownServer()
gechongrepl:PRIMARY>
2015-05-29T00:12:23.962-0700 I NETWORK  DBClientCursor::init call() failed
2015-05-29T00:12:23.965-0700 I NETWORK  trying reconnect to 127.0.0.1:27017 (127.0.0.1) failed
2015-05-29T00:12:23.966-0700 I NETWORK  reconnect 127.0.0.1:27017 (127.0.0.1) ok

Primary变为Secondary：
gechongrepl:SECONDARY>
gechongrepl:SECONDARY> use admin
switched to db admin
gechongrepl:SECONDARY> db.shutdownServer()

总结：

1：先关闭从节点、仲裁节点。或者先关闭仲裁节点，最后关闭从节点。则：主节点自动变为从节点

2：先关闭主节点，则从节点自动变为主节点，在仲裁节点关闭之前，新主节点不能关闭

初始化的时候主从节点受priority的影响

priority: 是优先级，默认为1，优先级0为被动节点，不能成为活跃节点。优先级不位0则按照有大到小选出活跃节点。

如果文章对您有用，扫一下支付宝的红包，不胜感激！

欢迎加入QQ群进行技术交流：656897351（各种技术、招聘、兼职、培训欢迎加入）

Leave a Reply Cancel reply

You must be logged in to post a comment.


report

Recommend

About Joyk


Aggregate valuable and interesting links.
Joyk means Joy of geeK