If MSF is using CCI, you may need to increase the value of the parameter CCIMSGQSZ on all systems to at least 2048. You can perform this change dynamically.
Here are the steps:
1) Visit the OPSVIEW panel 4.1.1 and change increase the value of the parameter CCIMSGQSZ to 2048 on all systems
2) Issue the command F OPSS,RESTART(MSF)on all systems
3) If you have the parameter MSFINITREXX set the name of the REXX that defines the MSF links then you don't need to perform any further action. If this parameter is not set, you need to run the REXX that defines the links manually (usually called MSFINIT).
Be aware that this procedure will drop all the MSF connections so you should schedule it to a period when it won't cause any troubles to your production environment.