What Can I Do If "online failed" Is Displayed After I Run the dmesg Command on RHEL 6.7

Symptom

The command output containing "online failed" is displayed after you run the dmesg | grep –i fail command on Red Hat Enterprise Linux (RHEL) 6.7, as shown in Figure 2-38.

Figure 2-38 Error information

Cause Analysis

The host includes memory ranges that are hot swappable in e820 tables during boot. This means that kernel tries to add them twice. Once as part of e820 initialization and second time when hotplug memory auto-online feature tries to add them. This message is benign and does not cause any problems besides the error messages during boot. All memory is still present once the server boots and no other problems have been observed.

Solution

Upgrade the kernel.

Download the kernel from http://people.redhat.com/~mvyletel/bz1255272/.

Upgrade the kernel as follows:

Figure 2-39 shows the packages that need to be upgrade. Run the rpm –Uvh kernel-XXX.rpm command, and run the reboot command to restart the server. Then run the dmesg | grep –i fail command, and check whether the command output contains "online failed".

Figure 2-39 Packages to be upgraded