diff --git a/core/definitions.mk b/core/definitions.mk
index 83a2f87..13a7cb4 100755
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -158,9 +158,9 @@ $(hide)$(IAFW_STRIP) --strip-all $(@:.sbl=.sym.elf) -o $(@:.sbl=.elf)
 
 $(hide) cp $(@:.sbl=.elf) $@
 
-
-python3 $(INTEL_PATH_BUILD)/containertool/GenContainer.py create -t NORMAL -cl ELF1:$@ -k $(INTEL_PATH_BUILD)/testkeys/OS1_TestKey_Priv_RSA2048.pem -o $(PRODUCT_OUT)/sbl_os
-
+$(hide)rm -rf $(PRODUCT_OUT)/cmdline1
+$(hide)touch $(PRODUCT_OUT)/cmdline1
+python3 $(INTEL_PATH_BUILD)/containertool/GenContainer.py create -t MULTIBOOT -cl CMD1:$(PRODUCT_OUT)/cmdline1 ELF1:$@ -k $(INTEL_PATH_BUILD)/testkeys/OS1_TestKey_Priv_RSA3072.pem -o $(PRODUCT_OUT)/sbl_os
 
 $(hide) if [ "$(PRIVATE_MODULE:debug=)" = fb4sbl-user ]; then \
 	zip -juy $(FB4SBL_SYMBOLS_ZIP) $(@:.sbl=.map) $(@:.sbl=.sym.elf); \
diff --git a/testkeys/OS1_TestKey_Priv_RSA3072.pem b/testkeys/OS1_TestKey_Priv_RSA3072.pem
new file mode 100644
index 0000000..aaf67b5
--- /dev/null
+++ b/testkeys/OS1_TestKey_Priv_RSA3072.pem
@@ -0,0 +1,40 @@
+-----BEGIN PRIVATE KEY-----
+MIIG/QIBADANBgkqhkiG9w0BAQEFAASCBucwggbjAgEAAoIBgQCe1F8phaFvpjrS
+2bRNvE+jgX47v7rzUkzB3yrUB54AgzpRxfQ8BQQrGwkpG4esJsuKGIyaZR1CkJfc
+pjnzkW7GsfK3qgUpufr60zoz9cRwQBWrWyFQ6zzI+iurdlwy8b5wHnHsuyVcQsix
+dfpVRRoLSsOQPp/dhA7p6KiJfo+1rMq6347qCMoOIQaNXbfh5Mrj51uTox+P1vG4
+wTJtYXw/bqqCh9yeLcgFL0j8aBOiI6ONMlIwTQufNmqNKHmT/7JhaAcPthl52ACL
+QSG+mJ42vFq4pIjDQQ/dcmcfP5QHPPZuLB+KHxotiS6/WzHC5/zZP3MButayeaVE
+iGxb225lBfqlvlr+eCBnXzdY6PxYFtqWVdAqXIO4r3xMQYNOCBzUBTjbiGo0Od2a
+dsn5oa55Wl578LUsbNHxkZtaQ4PxA50iVTVlYmubB2ulyq5iuyiWYVUBo90XisY1
+F5tW+q5shjInWkICjgXToBKq6/NPnPGL7UbYuUCu3snJxPa2SLsCAwEAAQKCAYAD
+t7jagfQ7ZsqtsMbVovjCPP+1alF37I87YnvgJqV+IZQ14cpLtVpZn/Jg8fIFB4tw
+Gg8AdilvK29CjOmCV/8dy4CA6Avi5CWJxXPxT2lfr0BSmHl5KWhs0949zzFtR9dL
+TIsiHWdMd4u3C6nmYQ2xAfj94Vlgl/y5YObBASNf/0FnimAP/lCsb/11RaJOOUq+
+duXf2MueVEuoJW2GvedonLCFCaUSVsP9yxOMROtgujDT1z+xPbxt55oq362o1y1O
+QrVjwAJWkuq2hrnXSknModuK9jxv9igKfd7Om+uPZQ6wUMmZqorqnZ5DwsUvWJ7+
+kwLQrIPDqddSFIvhKCirJMTlzBTwpyxwwSOQGq0vilC0Ayf9kMRh/2c3ZprzuhUz
+eIkZWcAqrrAkCrtAs2WErHbLNSm3UStbOCeilFbivgYVqkcTtvIP0uYuTdZxIiRI
+M/ztKyHT9DRrYEA/OTbeSSlS5fpdoVWtxBrti2OjmfgWYk/0sAegM60MncyC3rEC
+gcEA1BdZp3rfl8t4C37/8JoErfHrArMUvl8oMliZ785DCHUoPvc266M50MiACfNT
+/hmna0+PpaFu5t5QKId06wZdc6ovjJ5hcMTrjuFmP6ASHSUevqx6BVMxs+hF4mol
+gICaDS5k6y+fN3AiCHNUp5Jn6aFsj7pKOfLRdMs1jgrbiGx2qJ/EAK4UYS1/ntY6
+A9eEuzs6JCsipZX8X/LKVvcFxfPxbue41h7nHd19TPz3+Sgmxrm4jIjDJoV0CNE8
+WpZ9AoHBAL+2M4FdQXZdwgAE0whh4Xl+pE8t9ygpqiWbwRb0yu9S+QLnJ6Ag/oq5
+MVDE1GdiItS8lvrAN16Hz0gVVUdwTCLZnfHpHSTgwAn1liXtlL/eADXOt9F3zmLv
+usj+sTB8V3YcfYMQHLA2Z1bKgG384cB0nIhsVYGD5w5hH5V81fRJlADTBkFSQBFO
+EosfuEwZztrFH627pjzhs4pEllg4C4eGotaaYITuvBCUvc+yCdux7GwExYlFdycB
+WGAEj9uplwKBwQCUg0FJUHYvMc/+pNCNZxwtvX/l5QZ6g+F+16H7VQCFdJxY8v0n
+JaX/d9aIoTXIcahVMWISBifFTBjvOGL7i/p2Ws5u9hyfPZUA+P6DQRBODkcoF1he
+UDI2m0gMUm2uPN8iqcELGs6voDqEllXJ/W/8HggJ4NXHHCvlT8JRk3LEZcb1LuKt
+4zfsEFMUI0h+ljSgcsm0t+vL7WnKuhVLrjABvF7sXSCF9x+5PvZVqbHua1ozv6rl
+5YJZgAuPfQx5FnUCgcBlRZ6Xq+e023psACBqwSoWwCuUGDgD416aV1j9A3tgSXh5
+bBqmoEdWiNXgUNnTcyfrMWSgOYIGUb/R2FMgVdYiYsroy7g1jvRjTnRuvL5jTKbX
+xcecw6km4nTNUJ3Rex3IquwynARLobGdS4Pklj27KN63wmK49DDOi8ffc/6h+WxR
+sygOwaBOg+uPysXUjZ2UO6WsZQBAEQqC9BBnsdOFWD4VF5/9GRAHwksyuF40zByU
+Q0EGbseutys0LbTA2SkCgcBTyrPPWUm3x5iVYe86uCtav0prKuvOILvM0pPvc4ih
+MaoxD0rTmIS/CycnFEJwimdS/hlLQjP72ANij2mrBFTxsoki0V1FaT44/Z1bXLLN
+aDzsO/GYQoIaPtGuLGuLUOfVX1PSVDLHv4O7gmgWY0j/ABdCdos6dJR8PSqutrZ5
+KUrdXZWrXQ/bpHMw2Zm2oG4aPFWqzVnm9OnZhF4Ho95+sRkUIicLPmGFvHWG37jX
+vn1vfXIm+7k0p56vjCx0WK8=
+-----END PRIVATE KEY-----