今天登錄服務器發現報錯，報錯內容為：-bash: fork: Cannot allocate memory

[root@proxy01 ~]# ssh proxy02
Last login: Thu Mar 17 17:42:20 2022 from 192.168.80.2
-bash: fork: Cannot allocate memory
-bash-4.2# ^C

問題原因

[root@proxy01 ~]# ssh proxy02
Last login: Thu Mar 17 17:47:32 2022 from 192.168.80.2
查看最大進程數
[root@proxy02 ~]# sysctl kernel.pid_max
kernel.pid_max = 32768
查看進程數
[root@proxy02 ~]# ps -eLf | wc -l
32528
確認是進程數滿了導致的

問題解決

修改最大進程數后系統恢復
[root@proxy02 ~]# echo 1000000 > /proc/sys/kernel/pid_max
永久生效
[root@proxy02 ~]# echo "kernel.pid_max=1000000 " >> /etc/sysctl.conf
[root@proxy02 ~]# sysctl -p
...
kernel.pid_max = 1000000
[root@proxy02 ~]# sysctl kernel.pid_max
kernel.pid_max = 1000000