nginx平滑升级
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1. nginx平滑升级
当我们开发了一个新的nginx模块,须要升级nginx binary时,须要进行下面的步骤:
a) 替换老的nginx binary
[root@lg-miui-file-mfs09 sbin]# mv nginx nginx.old [root@lg-miui-file-mfs09 sbin]# scp guojun1@10.237.92.30:/usr/local/nginx/sbin/nginx . guojun1@10.237.92.30's password: nginxb) 向old master process 发送SIGUSR2信号[root@lg-miui-file-mfs09 sbin]# kill -s SIGUSR2 16236nginx.pid文件会被重命名为nginx.pid.oldbin,而且执行新的nginx binary文件,此时新老版本号会同一时候执行:
[root@lg-miui-file-mfs09 sbin]# ll ../logs/ total 14392 -rw-r--r-- 1 guojun1 500 893 May 30 10:58 error.log -rw-r--r-- 1 guojun1 500 5617929 May 12 13:12 nginx-access.log -rw-r--r-- 1 guojun1 500 9102050 May 13 22:39 nginx-error.log -rw-r--r-- 1 root root 6 May 30 10:58 nginx.pid -rw-r--r-- 1 root root 6 May 30 10:58 nginx.pid.oldbin [root@lg-miui-file-mfs09 sbin]# ps aux | grep nginx root 16236 0.0 0.0 92920 3064 ?c) 向old master process发送SIGWINCH此时,master会”优雅地”关闭它的工作进程:Ss 10:58 0:00 nginx: master process ./nginx root 16237 0.0 0.0 94992 3988 ? S 10:58 0:00 nginx: worker process root 16238 0.0 0.0 94992 3988 ? S 10:58 0:00 nginx: worker process root 16239 0.0 0.0 94992 3988 ?
S 10:58 0:00 nginx: worker process root 16385 0.0 0.0 92924 6072 ? S 10:58 0:00 nginx: master process ./nginx root 16386 0.0 0.0 94996 3908 ? S 10:58 0:00 nginx: worker process root 16387 0.0 0.0 94996 3980 ? S 10:58 0:00 nginx: worker process root 16388 0.0 0.0 94996 3980 ? S 10:58 0:00 nginx: worker process root 16445 0.0 0.0 103244 852 pts/4 S+ 10:58 0:00 grep nginx
[root@lg-miui-file-mfs09 sbin]# kill -s SIGWINCH 16236 [root@lg-miui-file-mfs09 sbin]# ps aux | grep nginx root 16236 0.0 0.0 92920 3072 ?d) 关闭old master假设查看log发送更新成功,能够关闭old master,此时向old master进程发送SIGQUIT,仅仅留下新的server执行。Ss 10:58 0:00 nginx: master process ./nginx root 16385 0.0 0.0 92924 6072 ?
S 10:58 0:00 nginx: master process ./nginx root 16386 0.0 0.0 94996 3908 ? S 10:58 0:00 nginx: worker process root 16387 0.0 0.0 94996 3980 ? S 10:58 0:00 nginx: worker process root 16388 0.0 0.0 94996 3980 ? S 10:58 0:00 nginx: worker process
[root@lg-miui-file-mfs09 sbin]# kill -s SIGQUIT 16236 [root@lg-miui-file-mfs09 sbin]# ps aux | grep nginx root 16385 0.0 0.0 92924 6072 ?S 10:58 0:00 nginx: master process ./nginx root 16386 0.0 0.0 94996 3908 ? S 10:58 0:00 nginx: worker process root 16387 0.0 0.0 94996 3980 ? S 10:58 0:00 nginx: worker process root 16388 0.0 0.0 94996 3980 ? S 10:58 0:00 nginx: worker process
2. 回滚
假设我们在关闭老的工作进行之后查看log发现新的nginx server执行有问题,我们能够回滚到老的版本号。其过程例如以下:
a) 启动老的worker 进程能够通过向old master 进程发送SIGHUP信号,让其启动老的worker 进程。
[root@lg-miui-file-mfs09 sbin]# ps aux | grep nginx root 16385 0.0 0.0 92924 6072 ? S 10:58 0:00 nginx: master process ./nginx root 44583 0.0 0.0 92924 6076 ?b) 关闭新的master进程和worker进程向新的master进程发送SIGQUIT信号。关闭新的master进程和worker进程;S 11:57 0:00 nginx: master process ./nginx root 44584 0.0 0.0 94996 3984 ? S 11:57 0:00 nginx: worker process root 44585 0.0 0.0 94996 3984 ? S 11:57 0:00 nginx: worker process root 44586 0.0 0.0 94996 3984 ?
S 11:57 0:00 nginx: worker process root 44757 0.0 0.0 94996 3908 ? S 11:58 0:00 nginx: worker process root 44758 0.0 0.0 94996 3980 ? S 11:58 0:00 nginx: worker process root 44759 0.0 0.0 94996 3980 ?
S 11:58 0:00 nginx: worker process
[root@lg-miui-file-mfs09 sbin]# kill -s SIGQUIT 44583 [root@lg-miui-file-mfs09 sbin]# ps aux | grep nginx root 16385 0.0 0.0 92924 6072 ? S 10:58 0:00 nginx: master process ./nginx root 44757 0.0 0.0 94996 3908 ? S 11:58 0:00 nginx: worker process root 44758 0.0 0.0 94996 3980 ? S 11:58 0:00 nginx: worker process root 44759 0.0 0.0 94996 3980 ? S 11:58 0:00 nginx: worker process
假设新的master进程因为某些原因hung住了没有关闭,能够向它们发送SIGTERM或者SIGKILL信号。当新的master进程退出后。老的master进程会将nginx.pid.oldbin文件重命名为nginx.pid.
參考文献:
Nginx:http://wiki.nginx.org/CommandLine#Upgrading_To_a_New_Binary_On_The_Fly