The following command fails:
# vxassist -g testdg make testvol 10g layout=concat-mirror
VxVM vxassist WARNING V-5-1-3111 Can not convert to desired layout
Creating non-layered volume
Comment from the source code.
* This function is for generic disk array support. Some operations are
* valid and supported for volumes based on disks from certain disk arrays,
* Currently, volumes based entirely on EMC Symmetrix disk arrays can be
* mirrored, grown, but not relayout or convert to layered volume.
The vxassist command will create a non-layered volume instead.
Creating a layered volume on an EMC Symmetrix is not supported.
All disks are EMC Symmetrix