Red Hat Enterprise Linux Server Cookbook

Adding RAM on the fly

As with CPUs, the possibility to add memory on the fly is an added value in mission-critical environments where downtime can literally cost a company millions of Euros.

The recipe presented here is quite simple, similar to the one on CPUs. Here, your guest needs to be prepared to use this functionality as well.

Getting ready

If you want to be able to add memory on the fly to a guest, it must be configured to support it. As with the CPU, this has to be activated. There are three ways to do this:

• The guest must be created with the maxmem option, as follows:

  --memory 2G,maxmemory=4G

• You can set the maximum memory using the virsh command, as follows:

  ~]# virsh setmaxmem --domain <guestname> --size <max mem> --live
  

• You can edit the ...