diff --git a/configure/os/CONFIG.Cross_64.RHEL7-x86_64 b/configure/os/CONFIG.Cross_64.RHEL7-x86_64
new file mode 100644
index 000000000..75e4038d1
--- /dev/null
+++ b/configure/os/CONFIG.Cross_64.RHEL7-x86_64
@@ -0,0 +1,21 @@
+# "cross compile" for RHEL7-x86_64 on other 64 bit Linux version
+# Expects RHEL7 RPMs c++ and readline-devel installed in $(SYSROOT)
+# This can be installed on RHEL7 with:
+#    yum install --installroot=$(SYSROOT) <packages>
+# (Assuming $(SYSROOT) is on a shared network volume.)
+# Optionally use a newer toolset (installed on $(SYSROOT)).
+
+include $(CONFIG)/os/CONFIG.linux-x86.linux-x86
+
+SYSROOT          = /opt/RHEL7
+TOOLSET_LOCATION = /opt/rh
+
+# Do NOT set GNU_BIN (or else ...)!
+TOOLSET_DIR      = $(TOOLSET:%=$(TOOLSET_LOCATION)/%/root)
+CC  = $(SYSROOT)$(TOOLSET_DIR)/bin/gcc
+CCC = $(SYSROOT)$(TOOLSET_DIR)/bin/g++
+# Set LD_LIBRARY_PATH and BFLAG only with TOOLSET
+LD_LIBRARY_PATH  = $(if $(TOOLSET),$(SYSROOT)$(TOOLSET_DIR)/lib64)
+BFLAG            = $(if $(TOOLSET),-B$(SYSROOT)$(TOOLSET_DIR)/bin)
+TARGET_CPPFLAGS += --sysroot=$(SYSROOT) $(BFLAG)
+TARGET_LDFLAGS  += --sysroot=$(SYSROOT) $(BFLAG)
diff --git a/configure/os/CONFIG.RHEL8-x86_64.RHEL7-x86_64 b/configure/os/CONFIG.RHEL8-x86_64.RHEL7-x86_64
new file mode 100644
index 000000000..b5222b603
--- /dev/null
+++ b/configure/os/CONFIG.RHEL8-x86_64.RHEL7-x86_64
@@ -0,0 +1,4 @@
+include $(CONFIG)/os/CONFIG.Cross_64.RHEL7-x86_64
+
+#TOOLSET = devtoolset-11
+#STD_CXXFLAGS = -std=c++17
diff --git a/configure/os/CONFIG.RHEL8-x86_64.RHEL8-x86_64 b/configure/os/CONFIG.RHEL8-x86_64.RHEL8-x86_64
index 3a8106990..693b45b58 100644
--- a/configure/os/CONFIG.RHEL8-x86_64.RHEL8-x86_64
+++ b/configure/os/CONFIG.RHEL8-x86_64.RHEL8-x86_64
@@ -4,5 +4,5 @@ include $(CONFIG)/os/CONFIG.linux-x86.linux-x86
 # Use gcc 11 from gcc-toolset-11
 GNU_BIN = /opt/rh/gcc-toolset-11/root/usr/bin
 # Fix bug in gcc-toolset-11 calling the old assembler
-TARGET_CFLAGS = -B$(GNU_BIN)
+TARGET_CFLAGS += -B$(GNU_BIN)
 STD_CXXFLAGS = -std=c++17
diff --git a/configure/os/CONFIG.RHEL8-x86_64.nilrt7-armv7a b/configure/os/CONFIG.RHEL8-x86_64.nilrt7-armv7a
new file mode 100644
index 000000000..451238772
--- /dev/null
+++ b/configure/os/CONFIG.RHEL8-x86_64.nilrt7-armv7a
@@ -0,0 +1 @@
+GNU_BIN=/opt/RHEL7/bin
diff --git a/configure/os/CONFIG_SITE.RHEL8-x86_64.Common b/configure/os/CONFIG_SITE.RHEL8-x86_64.Common
index dd06ba889..96b5560e1 100644
--- a/configure/os/CONFIG_SITE.RHEL8-x86_64.Common
+++ b/configure/os/CONFIG_SITE.RHEL8-x86_64.Common
@@ -4,9 +4,8 @@ include $(CONFIG)/os/CONFIG_SITE.linux-x86_64.Common
 CROSS_COMPILER_TARGET_ARCHS += RHEL8-x86_64-clang
 
 # Build for old RHEL7 64 bit
-#CROSS_COMPILER_TARGET_ARCHS += RHEL7-x86_64
+CROSS_COMPILER_TARGET_ARCHS += RHEL7-x86_64
 
 # NI Linux Real-Time 7.x
 # requires RPM gcc-c++-arm-linux-gnu
-# not available yet for RHEL8
-#CROSS_COMPILER_TARGET_ARCHS += nilrt7-armv7a
+CROSS_COMPILER_TARGET_ARCHS += nilrt7-armv7a