Estou executando o cluster Galera de 3 nós usando MariaDB-server-10.3.13-1.el7.centos.x86_64e vendo periodicamente os seguintes erros nos logs. Eu fiz o google sobre esse erro, mas não encontrei nenhuma boa resposta. Alguém sabe o que esse erro está tentando dizer?

Verifiquei a rede e a perda de pacotes e não encontrei nada relacionado a problemas de rede.

[root@ostack-infra-2-1-galera-container-56895f1b ~]# tail -f /var/log/mysql_logs/galera_server_error.log
2021-11-20 22:07:28 0 [Note] WSREP: Service thread queue flushed.
2021-11-20 22:07:28 24 [Note] WSREP: Synchronized with group, ready for connections
2021-11-20 22:07:28 24 [Note] WSREP: wsrep_notify_cmd is not defined, skipping notification.
2021-11-20 22:07:29 0 [Note] WSREP: Trying to continue unpaused monitor
2021-11-20 22:07:29 0 [Note] WSREP: Trying to continue unpaused monitor
2021-11-21  0:07:10 0 [Note] WSREP: (e951c46a, 'tcp://0.0.0.0:4567') connection to peer 4b57a7fb with addr tcp://172.28.15.69:4567 timed out, no messages seen in PT3S
2021-11-21  0:07:10 0 [Note] WSREP: (e951c46a, 'tcp://0.0.0.0:4567') turning message relay requesting on, nonlive peers: tcp://172.28.15.69:4567
2021-11-21  0:07:11 0 [Note] WSREP: (e951c46a, 'tcp://0.0.0.0:4567') reconnecting to 4b57a7fb (tcp://172.28.15.69:4567), attempt 0
2021-11-21  0:07:11 0 [Note] WSREP: (e951c46a, 'tcp://0.0.0.0:4567') connection established to 4b57a7fb tcp://172.28.15.69:4567
2021-11-21  0:07:15 0 [Note] WSREP: (e951c46a, 'tcp://0.0.0.0:4567') turning message relay requesting off

Estamos executando o servidor kea DHCP com MySQL DB e hoje encontramos o seguinte erro e depois de pesquisar no Google todos dizendo que poderia ser um bug do MySQL, então queria ver se é realmente um bug ou problema de implementação.

MariaDB-server-10.2.15-1.el7.centos.x86_64 (cluster galera de 3 nós)

2020-03-07 01:59:16.484 INFO  [kea-dhcp4.leases/29796] DHCP4_LEASE_ALLOC [hwtype=1 00:0c:29:ae:77:cb], cid=[no info], tid=0x80b9c710: lease 10.10.10.22 has been allocated
2020-03-07 02:04:29.625 ERROR [kea-dhcp4.alloc-engine/29796] ALLOC_ENGINE_V4_ALLOC_ERROR [hwtype=1 00:19:85:f0:1c:89], cid=[no info], tid=0xd7790768: error during attempt to allocat
e an IPv4 address: unable to execute for <UPDATE lease4 SET address = ?, hwaddr = ?, client_id = ?, valid_lifetime = ?, expire = ?, subnet_id = ?, fqdn_fwd = ?, fqdn_rev = ?, hostna
me = ?, state = ? WHERE address = ?>, reason: Incorrect datetime value: '2020-03-08 02:04:29' for column 'expire' at row 1 (error code 1292)

Estou executando a nuvem openstack e usa o banco de dados mysql que éMariaDB 10.1.30

Às vezes estou vendo a conexão redefinida de vários clientes, para tentar descobrir o que está acontecendo no banco de dados, estou vendo o seguinte status relacionado à conexão, mas quero ter certeza de quais conselhos de especialistas aqui, devo aumentar max_connectionno mysql?

Eu tenho 64 GB de memória no servidor, mas também outros componentes em execução nos servidores, então, tentando evitar overcommit memory, qual é a relação entre threads e contagem de conexões?

MariaDB [(none)]> SHOW STATUS LIKE '%onn%';
+-----------------------------------------------+----------+
| Variable_name                                 | Value    |
+-----------------------------------------------+----------+
| Aborted_connects                              | 5951     |
| Connection_errors_accept                      | 0        |
| Connection_errors_internal                    | 0        |
| Connection_errors_max_connections             | 406      |
| Connection_errors_peer_address                | 0        |
| Connection_errors_select                      | 0        |
| Connection_errors_tcpwrap                     | 0        |
| Connections                                   | 23430967 |
| Max_used_connections                          | 1601     |
| Performance_schema_session_connect_attrs_lost | 0        |
| Slave_connections                             | 0        |
| Slaves_connected                              | 0        |
| Ssl_client_connects                           | 0        |
| Ssl_connect_renegotiates                      | 0        |
| Ssl_finished_connects                         | 0        |
| Threads_connected                             | 1284     |
| wsrep_connected                               | ON       |
+-----------------------------------------------+----------+
17 rows in set (0.00 sec)

Tópicos

MariaDB [(none)]> SHOW STATUS LIKE '%Threads%';
+-------------------------+-------+
| Variable_name           | Value |
+-------------------------+-------+
| Delayed_insert_threads  | 0     |
| Slow_launch_threads     | 0     |
| Threadpool_idle_threads | 0     |
| Threadpool_threads      | 0     |
| Threads_cached          | 47    |
| Threads_connected       | 1284  |
| Threads_created         | 86815 |
| Threads_running         | 1     |
+-------------------------+-------+
8 rows in set (0.01 sec)

Aqui está meu arquivo my.cfg.

[client]
port = 3306
socket = "/var/lib/mysql/mysql.sock"


[mysqld_safe]
socket = "/var/lib/mysql/mysql.sock"
nice = 0
log_error = /var/log/mysql_logs/galera_server_error.log


[mysql]
default-character-set = utf8


[mysqld]
user = mysql
collation-server = utf8_general_ci
init-connect = 'SET NAMES utf8'
character-set-server = utf8
datadir = /var/lib/mysql
bind-address = ::
server-id = 200

# LOGGING #
log-queries-not-using-indexes = 0
slow-query-log = 0
slow-query-log-file = /var/log/mysql_logs/mysql-slow.log
log_error = /var/log/mysql_logs/galera_server_error.log
log-bin = /var/lib/mysql/mariadb-bin
log-bin-index = /var/lib/mysql/mariadb-bin.index
expire-logs-days = 7
log_slave_updates = 1
log_bin_trust_function_creators = 1

# SAFETY #
max-allowed-packet = 16M
max-connect-errors = 1000000

# NOTE: If galera_max_connections is not configured by user, the number of max
# connections is defined by ( host_vcpus * 100 ) with a capping value of 1600.
# This value is the lowest integer based on the ansible facts gathered from
# every galera node.
# Computing the connections value using the lowest denominator maintains
# cluster integrity by not attempting to over commit to a less capable machine.
# These are the computed max_connections based on the cluster data
# [1600, 1600, 1600]
max_connections = 1600

wait_timeout = 3600

# CACHES AND LIMITS #
tmp-table-size = 32M
max-heap-table-size = 32M
query-cache-type = 0
query-cache-size = 0M
thread-cache-size = 50
open-files-limit = 65535
table-definition-cache = 4096
table-open-cache = 10240

# INNODB #
innodb-flush-method = O_DIRECT
innodb-log-file-size = 1024M
innodb-flush-log-at-trx-commit = 1
innodb-file-per-table = 1
innodb-buffer-pool-size = 4096M

# Depending on number of cores and disk sub
innodb-read-io-threads = 4
innodb-write-io-threads = 4
innodb-doublewrite = 1
innodb-log-buffer-size = 128M
innodb-buffer-pool-instances = 8
innodb-log-files-in-group = 2
innodb-thread-concurrency = 64

# avoid statistics update when doing e.g show tables
innodb_stats_on_metadata = 0

[mysqldump]
quick
quote-names
max_allowed_packet = 16M


!includedir /etc/mysql/conf.d/

ATUALIZAÇÃO - 1

Após o aumento max_connectionde 1600 para 3200, corrija o problema de interrupção da conexão