PRVG-11069 : IP address “169.254.0.2” of network interface “idrac” on the node “primrac1” would conflict with HAIP usage

Problem:

Oracle 18c GI configuration precheck was failing with the following error:

Summary of node specific errors 

primrac2  - PRVG-11069 : IP address "169.254.0.2" of network interface "idrac" on the node "primrac2" would conflict with HAIP usage.  
- Cause:  One or more network interfaces have IP addresses in the range (169.254..), the range used by HAIP which can create routing conflicts.  
- Action:  Make sure there are no IP addresses in the range (169.254..) on any network interfaces. 

primrac1  - PRVG-11069 : IP address "169.254.0.2" of network interface "idrac" on the node "primrac1" would conflict with HAIP usage. 
- Cause:  One or more network interfaces have IP addresses in the range (169.254..), the range used by HAIP which can create routing conflicts.  
- Action:  Make sure there are no IP addresses in the range (169.254..) on any network interfaces.  

On each node additional network interface – named idrac was started with the ip address 169.254.0.2. I tried to set static ip address in /etc/sysconfig/network-scripts/ifcfg-idrac , also tried to bring the interface down – but after some time interface was starting up automatically and getting the same ip address.

Cluster nodes were DELL servers with Dell Remote Access Controller(iDRAC) Service Module installed. For more information about this module installation/deinstallation… can be found here https://topics-cdn.dell.com/pdf/idrac-service-module-v32_users-guide_en-us.pdf

Servers were configured by system administrator and was not clear why this module was there, we are not using iDRAC module and the only option that we had was to remove/uninstall that module. (configuring module should also be possible to avoid such situation, but we keep our servers as clean as possible without having unsed services)

Solution:

Uninstalled iDRAC module (also expained in the above pdf):

# rpm -e dcism 

After uninstalling it idrac interface did not started anymore, so we could continue GI configuration.

PRVF-6402 : Core file name pattern is not same on all the nodes

Problem:

Oracle 18c GI configuration prerequisite checks failed with the following error:

PRVF-6402 : Core file name pattern is not same on all the nodes. Found core filename pattern "core" on nodes "primrac1". Found core filename pattern "core.%p" on nodes "primrac2".  
- Cause:  The core file name pattern is not same on all the nodes.  
- Action:  Ensure that the mechanism for core file naming works consistently on all the nodes. Typically for Linux, the elements to look into are the contents of two files /proc/sys/kernel/core_pattern or /proc/sys/kernel/core_uses_pid. Refer OS vendor documentation for platforms AIX, HP-UX, and Solaris.

Comparing parameter values on both nodes:

[root@primrac1 ~]# cat /proc/sys/kernel/core_uses_pid
0
[root@primrac2 ~]# cat /proc/sys/kernel/core_uses_pid
1 

[root@primrac1 ~]# sysctl -a|grep core_uses_pid
kernel.core_uses_pid = 0

[root@primrac2 ~]# sysctl -a|grep core_uses_pid
kernel.core_uses_pid = 1

Strange fact was that this parameter was not defined explicitly in sysctl.conf file, but still had different default values:

[root@primrac1 ~]# cat /etc/sysctl.conf |grep core_uses_pid
[root@primrac2 ~]# cat /etc/sysctl.conf |grep core_uses_pid 

Solution:

I’ve set parameter to 1 explicitly in sysctl.conf on both nodes:

[root@primrac1 ~]# cat /etc/sysctl.conf |grep core_uses_pid
kernel.core_uses_pid=1 

[root@primrac2 ~]# cat /etc/sysctl.conf |grep core_uses_pid
kernel.core_uses_pid=1

[root@primrac1 ~]# sysctl -p 
[root@primrac2 ~]# sysctl -p

[root@primrac1 ~]# sysctl -a|grep core_uses_pid 
kernel.core_uses_pid = 1

[root@primrac2 ~]# sysctl -a|grep core_uses_pid 
kernel.core_uses_pid = 1

Pressed Check Again button and GI configuration succeeded.