Enable CentOS 32-bit support for memory larger than 4 GB

When a CentOS5.6 machine needs to upgrade the memory to 6 GB, the system is found to be 32-bit, so the search can enable the 32-bit system to support 4 GB memory or above. How does one make linux/Centos32-bit support 8 GB memory? The kernel-based PAE installation supports a method larger than 4 GB memory. Linux/Centos32bitOS does not support 4 GB memory or above by default. you can install a kernel-PAE patch to solve this problem. you 'd better back up a snapshot of the virtual machine before the operation to avoid unexpected recovery.

When a CentOS 5.6 machine needs to upgrade the memory to 6 GB, the system is found to be 32-bit, so the search can enable the 32-bit system to support 4 GB memory or above.

How does one enable 32-bit linux/Centos to support 8 GB memory? The kernel-based PAE installation supports a method larger than 4 GB memory. Linux/Centos 32bit OS does not support 4 GB memory or above by default. you can install a kernel-PAE patch to solve this problem. it is best to back up a snapshot of the virtual machine before the operation, in case of an accident, it can be restored to normal.

The following are the steps:

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[root@www.ctohome.com]# freetotal       used       freeshared    buffers     cachedMem:       3881968     637928    3244040          0     111292     461680-/+ buffers/cache:      64956    3817012Swap:      4192924          0    4192924[root@www.ctohome.com]# yum install kernel-PAELoaded plugins: fastestmirrorLoading mirror speeds from cached hostfilecentos-burstnet                                                                                                                                          | 1.1 kB     00:00  updates-burstnet                                                                                                                                         | 1.9 kB     00:00  Setting up Install ProcessResolving Dependencies--> Running transaction check---> Package kernel-PAE.i686 0:2.6.18-194.32.1.el5 setto be installed--> Finished Dependency ResolutionDependencies Resolved================================================================================================================================================================================Package                                 Arch                              Version                                          Repository                                     Size================================================================================================================================================================================Installing:kernel-PAE                              i686                              2.6.18-194.32.1.el5                              updates-burstnet                               17 MTransaction Summary================================================================================================================================================================================Install       1 Package(s)Upgrade       0 Package(s)Total download size: 17 MIs this ok [y/N]: yDownloading Packages:kernel-PAE-2.6.18-194.32.1.el5.i686.rpm                                                                                                                  |  17 MB     00:01  Running rpm_check_debugRunning Transaction TestFinished Transaction TestTransaction Test SucceededRunning TransactionInstalling     : kernel-PAE                                                                                                                                               1/1Installed:kernel-PAE.i686 0:2.6.18-194.32.1.el5                                                                                                                                     Complete![root@www.ctohome.com]# freetotal       used       freeshared    buffers     cachedMem:       3881968     637928    3244040          0     111292     461680-/+ buffers/cache:      64956    3817012Swap:      4192924          0    4192924[root@www.ctohome.com]# vi /boot/grub/grub.confdefault=0    # (Change default = 1 to default = 0)timeout=5splashimage=(hd0,0)/grub/splash.xpm.gzhiddenmenutitle CentOS (2.6.18-194.32.1.el5PAE)    # (If this line of PAE exists, the pae kernel is successfully installed)root (hd0,0)kernel /vmlinuz-2.6.18-194.32.1.el5PAE ro root=LABEL=/initrd /initrd-2.6.18-194.32.1.el5PAE.imgtitle CentOS (2.6.18-194.32.1.el5)root (hd0,0)kernel /vmlinuz-2.6.18-194.32.1.el5 ro root=LABEL=/initrd /initrd-2.6.18-194.32.1.el5.imgtitle CentOS (2.6.18-194.el5)root (hd0,0)kernel /vmlinuz-2.6.18-194.el5 ro root=LABEL=/initrd /initrd-2.6.18-194.el5.img[root@www.ctohome.com]# Reboot (restart the server here and pray that sometimes the motherboard or Nic is not supported, you can only contact the IDC)Broadcast message from root (pts/0) (Thu May 19 18:52:34 2011):The system is going down forreboot NOW![root@www.ctohome.com]# freetotal       used       freeshared    buffers     cachedMem:       8295488     215248    8080240          0      19460     142592-/+ buffers/cache:      53196    8242292Swap:      4192924          0    4192924

The upgrade is complete and supports large memory.