informix 9.40.UC9X4升级到11.50.UC6初始化失败
现象描述： "informix 9.40.UC9X4升级到11.50.UC6，oninit –ivy初始化报错：
oninit -ivy
Checking group membership to determine server run mode...succeeded
Reading configuration file '/opt/informix/etc/onconfig'...succeeded
Creating /INFORMIXTMP/.infxdirs...succeeded
Checking config parameters...succeeded
Allocating and attaching to shared memory...FAILED
oninit: Fatal error in shared memory creation
WARNING: server initialization failed, or possibly timed out (if -w was used).
Check the message log, online.log, for errors.
"
告警信息： 无
原因分析： "初始化失败，首先看online.log日志，onstat -m看到如下错误信息：
10:39:21 IBM Informix Dynamic Server Started.
10:39:21 shmget: [EEXIST][17]: key 52564801: shared memory already exists
10:39:21 mt_shm_init: can't create resident segment
由shared memory already exists可以得知为共享内存问题"
处理过程： "1、修改onconfig文件的SHMBASE参数，oninit -ivy
Checking group membership to determine server run mode...succeeded
Reading configuration file '/opt/informix/etc/onconfig'...succeeded
Creating /INFORMIXTMP/.infxdirs...succeeded
Checking config parameters...succeeded
Allocating and attaching to shared memory...FAILED
oninit: Fatal error in shared memory creation
WARNING: server initialization failed, or possibly timed out (if -w was used).
Check the message log, online.log, for errors.
2、为了彻底释放占用的共享内存地址，reboot重启机器；oninit -ivy初始化成功。"
建议与总结： informix故障，首先查看online.log日志，根据日志报错定位问题
oninit -ivy
Checking group membership to determine server run mode...succeeded
Reading configuration file '/opt/informix/etc/onconfig'...succeeded
Creating /INFORMIXTMP/.infxdirs...succeeded
Checking config parameters...succeeded
Allocating and attaching to shared memory...FAILED
oninit: Fatal error in shared memory creation
WARNING: server initialization failed, or possibly timed out (if -w was used).
Check the message log, online.log, for errors.
"
告警信息： 无
原因分析： "初始化失败，首先看online.log日志，onstat -m看到如下错误信息：
10:39:21 IBM Informix Dynamic Server Started.
10:39:21 shmget: [EEXIST][17]: key 52564801: shared memory already exists
10:39:21 mt_shm_init: can't create resident segment
由shared memory already exists可以得知为共享内存问题"
处理过程： "1、修改onconfig文件的SHMBASE参数，oninit -ivy
Checking group membership to determine server run mode...succeeded
Reading configuration file '/opt/informix/etc/onconfig'...succeeded
Creating /INFORMIXTMP/.infxdirs...succeeded
Checking config parameters...succeeded
Allocating and attaching to shared memory...FAILED
oninit: Fatal error in shared memory creation
WARNING: server initialization failed, or possibly timed out (if -w was used).
Check the message log, online.log, for errors.
2、为了彻底释放占用的共享内存地址，reboot重启机器；oninit -ivy初始化成功。"
建议与总结： informix故障，首先查看online.log日志，根据日志报错定位问题