Patroni & Etcd
环境说明
项目 | 说明 | 备注 |
操作系统 | RockyLinux8 | |
系统内核 | 5.14.0-362.8.1.el9_3.x86_64 | |
Patroni | 4.0.0 | /opt/patroni/patroni |
Etcd | 3.5.15 | /opt/etcd-3.5.15 |
PostgreSQL | 14.9 | |
主机IP | 10.16.18.160~10.16.18.162 |
安装配置Etcd
Etcd 是一个可靠的分布式 key-value 存储系统,主要用于配置共享和服务注册和发现。Patroni主要使用其存储PostgreSQL集群的信息。
以下操作需要在三台机器上都要执行。
下载安装包
cd /opt
wget https://github.com/etcd-io/etcd/releases/download/v3.5.15/etcd-v3.5.15-linux-amd64.tar.gz
解压
tar xzf etcd-v3.5.15-linux-amd64.tar.gz
修改下目录名称
mv etcd-v3.5.15-linux-amd64 etcd-3.5.15
创建一个日志目录
mkdir -p /opt/etcd-3.5.15/logs
PG01上添加配置文件
/opt/etcd-3.5.15/etcd.conf
name: patroni01
data-dir: /opt/etcd-3.5.15
listen-peer-urls: http://10.16.18.160:2380
listen-client-urls: http://10.16.18.160:2379,http://127.0.0.1:2379
initial-cluster-state: new
initial-cluster-token: etcd-cluster
advertise-client-urls: http://10.16.18.160:2379
initial-advertise-peer-urls: http://10.16.18.160:2380
initial-cluster: patroni01=http://10.16.18.160:2380,patroni02=http://10.16.18.161:2380,patroni03=http://10.16.18.162:2380
如果添加enable-v2: true,那么对应的Patroni配置文件中应当是etcd,而不是etcd3。
PG02上添加配置文件
/opt/etcd-3.5.15/etcd.conf
name: patroni02
data-dir: /opt/etcd-3.5.15
listen-peer-urls: http://10.16.18.161:2380
listen-client-urls: http://10.16.18.161:2379,http://127.0.0.1:2379
initial-cluster-state: new
initial-cluster-token: etcd-cluster
advertise-client-urls: http://10.16.18.161:2379
initial-advertise-peer-urls: http://10.16.18.161:2380
initial-cluster: patroni01=http://10.16.18.160:2380,patroni02=http://10.16.18.161:2380,patroni03=http://10.16.18.162:2380
PG03上添加配置文件
/opt/etcd-3.5.15/etcd.conf
name: patroni03
data-dir: /opt/etcd-3.5.15
listen-peer-urls: http://10.16.18.162:2380
listen-client-urls: http://10.16.18.162:2379,http://127.0.0.1:2379
initial-cluster-state: new
initial-cluster-token: etcd-cluster
advertise-client-urls: http://10.16.18.162:2379
initial-advertise-peer-urls: http://10.16.18.162:2380
initial-cluster: patroni01=http://10.16.18.160:2380,patroni02=http://10.16.18.161:2380,patroni03=http://10.16.18.162:2380
在三台机器上配置系统服务
/usr/lib/systemd/system/etcd.service
[Unit]
Description=Etcd Server
Documentation=https://github.com/coreos/etcd
After=network.target
WorkingDirectory=/opt/etcd-3.5.15/etcd
[Service]
User=root
Type=notify
ExecStart=/opt/etcd-3.5.15/etcd --config-file /opt/etcd-3.5.15/etcd.conf --log-level error
Restart=on-failure
RestartSec=10s
LimitNOFILE=40000
StandardOutput=file:/opt/etcd-3.5.15/logs/etcd.log
StandardError=file:/opt/etcd-3.5.15/logs/etcd-error.log
[Install]
WantedBy=multi-user.target
在三台机器上启动etcd服务,初始化etcd数据库
systemct daemon-reload && systemctl start etcd
如果想设置为开机自启,加上systemctl enable etcd
查看节点的状态
/opt/etcd-3.5.15/etcdctl endpoint health --cluster -w table
[root@PG01 opt]# /opt/etcd-3.5.15/etcdctl endpoint health --cluster -w table
+--------------------------+--------+------------+-------+
| ENDPOINT | HEALTH | TOOK | ERROR |
+--------------------------+--------+------------+-------+
| http://10.16.18.160:2379 | true | 1.018523ms | |
| http://10.16.18.162:2379 | true | 1.247401ms | |
| http://10.16.18.161:2379 | true | 1.384808ms | |
+--------------------------+--------+------------+-------+
看到输出结果如上说明成功了,否则查看日志文件
/opt/etcd-3.5.15/logs/etcd-error.log查找原因。
网上有些配置文件示例是下面这样的,这种配置是环境变量的方式,不能通过etcd --config-file的方式执行。
#[Member]
ETCD_NAME="patroni01"
ETCD_DATA_DIR="/opt/etcd-3.5.15/data"
ETCD_LISTEN_PEER_URLS="http://10.16.18.160:2380"
ETCD_LISTEN_CLIENT_URLS="http://10.16.18.160:2379,http://127.0.0.1:2379"
#[Clustering]
ETCD_ENABLE_V2=true
ETCD_INITIAL_CLUSTER_STATE="new"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_ADVERTISE_CLIENT_URLS="http://10.16.18.160:2379"
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://10.16.18.160:2380"
ETCD_INITIAL_CLUSTER="patroni01=http://10.16.18.160:2380,patroni02=http://10.16.18.161:2380,patroni03=http://10.16.18.162:2380"
与其对应的是在
/usr/lib/systemd/system/etcd.service中增加EnvironmentFile
[Service]
EnvironmentFile=-/opt/etcd-v3.5.0/config/etcd.conf
安装配置Patroni
以下操作三台机器上都要执行。
安装Python3
需要先安装Python3,网上类似的文章很多,这里不再赘述,或者直接使用中启乘数提供的编译好的Python包(是给他们CLup软件用的),我之前装过,所以这里不再安装Python环境。
这里给一个安装示例,只有el7和el8的版本
cd /opt
wget https://gitee.com/csudata/csupy3.9.16/releases/download/1.0/csupy3.9.16.el8.tar.xz
tar xf csupy3.9.16.el8.tar.xz
el7的话替换下el8即可。
如果是其他的操作系统,又不想折腾编译Python3,也可以装一个CLup的开源版本(另一款PostgreSQL高可用软件,带有Web界面,建议有时间的话可以装一套用用),软件安装时会自动安装一个Python3的环境。
其安装命令如下,参考文档:
https://www.csudata.com/clup/manual/5.x/10147
wget -qO /tmp/clup.sh --no-check-certificate https://get.csudata.com/csuinst/clup.sh && bash /tmp/clup.sh openclup install
在其中一套安装即可,如果想要试用CLup的话在其他机器上安装其Agent端,要不就是直接tar一下Python3环境,然后scp过去再解压。
上面的tar包解压或是安装CLup后的Python环境如下
.
├── csupy3.9.16
└── csu_pyenv
- csupy3.9.16:Python3的软件目录
- csu_pyenv:安装了工具包的虚拟环境
需要先添加下环境变量~/.bashrc
export PATH=/opt/csupy3.9.16/bin:$PATH
export LD_LIBRARY_PATH=/opt/csupy3.9.16/lib:$LD_LIBRARY_PATH
注意替换路径为自己的实际路径。
安装Patroni
Patroni安装比较简单,直接pip安装,下面还需安装psycopg2-binary(Python 连接PostgreSQL的库)
pip3 install psycopg2-binary -i https://mirrors.aliyun.com/pypi/simple/
pip3 install patroni[etcd] -i https://mirrors.aliyun.com/pypi/simple/
配置Patroni
创建目录
mkdir -p /opt/patroni/conf
mkdir -p /opt/patroni/logs
PG01上添加配置文件
/opt/patroni/conf/patroni_pg.yml
scope: pg14-cluster
name: patroni01
# log
log:
level: INFO
traceback_level: ERROR
dir: /opt/patroni/logs
file_num: 10
# file_size: 26214400
restapi:
listen: 10.16.18.160:8008
connect_address: 10.16.18.160:8008
etcd3:
hosts: 10.16.18.160:2379,10.16.18.161:2379,10.16.18.162:2379
bootstrap:
# this section will be written into Etcd:///config after initializing new cluster
# and all other cluster members will use it as a `global configuration`
dcs:
ttl: 30
loop_wait: 10
retry_timeout: 10
maximum_lag_on_failover: 1048576
master_start_timeout: 300
synchronous_mode: false
postgresql:
use_pg_rewind: true
use_slots: true
parameters:
listen_addresses: "*"
port: 5414
wal_level: logical
hot_standby: "on"
max_wal_senders: 10
max_replication_slots: 10
wal_log_hints: "on"
postgresql:
listen: 10.16.18.160:5414
connect_address: 10.16.18.160:5414
database: template1
data_dir: /data/pgdata14
bin_dir: /usr/csupg-14.9/bin
pgpass: /home/pg14/.pgpass
#callbacks:
#on_start:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
#on_stop:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
#on_role_change:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
authentication:
replication:
username: postgres
password: postgres
superuser:
username: postgres
password: postgres
rewind:
username: postgres
password: postgres
watchdog:
mode: off # Allowed values: off, automatic, required
device: /dev/watchdog
safety_margin: 5
tags:
nofailover: false
noloadbalance: false
clonefrom: false
nosync: false
PG02上添加配置文件
/opt/patroni/conf/patroni_pg.yml
scope: pg14-cluster
name: patroni02
# log
log:
level: INFO
traceback_level: ERROR
dir: /opt/patroni/logs
file_num: 10
# file_size: 26214400
restapi:
listen: 10.16.18.161:8008
connect_address: 10.16.18.161:8008
etcd3:
hosts: 10.16.18.160:2379,10.16.18.161:2379,10.16.18.162:2379
bootstrap:
# this section will be written into Etcd:///config after initializing new cluster
# and all other cluster members will use it as a `global configuration`
dcs:
ttl: 30
loop_wait: 10
retry_timeout: 10
maximum_lag_on_failover: 1048576
master_start_timeout: 300
synchronous_mode: false
postgresql:
use_pg_rewind: true
use_slots: true
parameters:
listen_addresses: "*"
port: 5414
wal_level: logical
hot_standby: "on"
max_wal_senders: 10
max_replication_slots: 10
wal_log_hints: "on"
postgresql:
listen: 10.16.18.161:5414
connect_address: 10.16.18.161:5414
database: template1
data_dir: /data/pgdata14
bin_dir: /usr/csupg-14.9/bin
pgpass: /home/pg14/.pgpass
#callbacks:
#on_start:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
#on_stop:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
#on_role_change:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
authentication:
replication:
username: postgres
password: postgres
superuser:
username: postgres
password: postgres
rewind:
username: postgres
password: postgres
watchdog:
mode: off # Allowed values: off, automatic, required
device: /dev/watchdog
safety_margin: 5
tags:
nofailover: false
noloadbalance: false
clonefrom: false
nosync: false
PG03上添加配置文件
/opt/patroni/conf/patroni_pg.yml`
scope: pg14-cluster
name: patroni03
# log
log:
level: INFO
traceback_level: ERROR
dir: /opt/patroni/logs
file_num: 10
# file_size: 26214400
restapi:
listen: 10.16.18.162:8008
connect_address: 10.16.18.162:8008
etcd3:
hosts: 10.16.18.160:2379,10.16.18.161:2379,10.16.18.162:2379
bootstrap:
# this section will be written into Etcd:///config after initializing new cluster
# and all other cluster members will use it as a `global configuration`
dcs:
ttl: 30
loop_wait: 10
retry_timeout: 10
maximum_lag_on_failover: 1048576
master_start_timeout: 300
synchronous_mode: false
postgresql:
use_pg_rewind: true
use_slots: true
parameters:
listen_addresses: "*"
port: 5414
wal_level: logical
hot_standby: "on"
max_wal_senders: 10
max_replication_slots: 10
wal_log_hints: "on"
postgresql:
listen: 10.16.18.162:5414
connect_address: 10.16.18.162:5414
database: template1
data_dir: /data/pgdata14
bin_dir: /usr/csupg-14.9/bin
pgpass: /home/pg14/.pgpass
#callbacks:
#on_start:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
#on_stop:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
#on_role_change:/u01/app/halo/product/shield/patroni/scripts/patroni_callback.sh
authentication:
replication:
username: postgres
password: postgres
superuser:
username: postgres
password: postgres
rewind:
username: postgres
password: postgres
watchdog:
mode: off # Allowed values: off, automatic, required
device: /dev/watchdog
safety_margin: 5
tags:
nofailover: false
noloadbalance: false
clonefrom: false
nosync: false
系统服务
/usr/lib/systemd/system/patroni.service
[Unit]
Description=Patroni Cluster
After=syslog.target network.target
[Service]
Type=simple
User=pg14
Group=pg14
# Set PATH LD_LIBRARY_PATH, they will be passed to OS env variables when call pg_ctl by patroni
Environment="LD_LIBRARY_PATH=/usr/csupg-14.9/lib:/opt/csupy3.9.16/lib"
# Start the patroni process
ExecStart=/opt/csupy3.9.16/bin/patroni /opt/patroni/conf/patroni_pg.yml
# Send HUP to reload from patroni.yml
ExecReload=/bin/kill -s HUP $MAINPID
# only kill the patroni process, not it's children, so it will gracefully stop Halo
KillMode=process
# Give a reasonable amount of time for the server to start up/shut down
TimeoutSec=30
# Do not restart the service if it crashes, we want to manually inspect database on failure
Restart=no
[Install]
WantedBy=multi-user.target
注意替换Environment中的值为自己的实际路径。
修改文件属主
chown -R pg14:pg14 /opt/patroni
启动服务
systemctl daemon-reload && systemctl start patroni
查看集群的状态
patronictl -c /opt/patroni/conf/patroni_pg.yml list
这里Leader节点显示有些参数会在重启后生效,实际上是patroni在启动时会根据patroni的配置文件修改数据的参数。
剩下的两个Replica节点没有显示未生效的参数的原因是中间启动备节点的patroni有问题,后面重搭了备库,需要注意的是执行pg_basebackup后要修改下参数
# postgresql.conf
listen_addresses = 10.16.18.161
# postgresql.auto.conf
primary_conninfo="application_name=patroni02 ..."
注意:这里的地址换成自己的当前备库的实际地址,primary_conninfo中是增加application_name=,而不是配置成上面那样。
问题解决
etcd启动时报错
[root@PG01 logs]# /opt/etcd-3.5.15/etcd --config-file /opt/etcd-3.5.15/etcd.conf --log-level debug
{"level":"info","ts":"2024-08-30T10:00:16.034302+0800","caller":"etcdmain/etcd.go:73","msg":"Running: ","args":["/opt/etcd-3.5.15/etcd","--config-file","/opt/etcd-3.5.15/etcd.conf","--log-level","debug"]}
{"level":"warn","ts":"2024-08-30T10:00:16.034328+0800","caller":"etcdmain/etcd.go:75","msg":"failed to verify flags","error":"error unmarshaling JSON: while decoding JSON: json: cannot unmarshal string into Go struct field configYAML.log-outputs of type []string"}
检查配置文件,可能有些参数名称不对或者设置不对。
cluster id 不对
问题描述:
启动Patroni后日志中总是报错:
node patroni02 belongs to a different cluster: 7223643286119069904 !=7384703923858607267
原因:
可能是旧的集群数据没有清理掉
解决版本:清理旧集群数据,所有节点都要做
- 停止Patroni服务
- systemctl stop patroni
- 停止etcd服务
- systemctl stop etcd
- 清理或者重命名旧集群数据
- cd /etc/etcdxxx/
mv data data_old - 启动etcd
- systemctl start etcd
- 启动patroni
- systemctl start patroni