diff --git a/units/console-getty.service.m4.in b/units/console-getty.service.m4.in
index 413d94094b..d9d0cba4d9 100644
--- a/units/console-getty.service.m4.in
+++ b/units/console-getty.service.m4.in
@@ -16,7 +16,10 @@ After=rc-local.service
 Before=getty.target
 
 [Service]
-ExecStart=-/sbin/agetty --noclear --keep-baud console 115200,38400,9600 $TERM
+# The '-o' option value tells agetty to replace 'login' arguments with an
+# option to preserve environment (-p), followed by '--' for safety, and then
+# the entered username.
+ExecStart=-/sbin/agetty -o '-p -- \\u' --noclear --keep-baud console 115200,38400,9600 $TERM
 Type=idle
 Restart=always
 RestartSec=0
diff --git a/units/container-getty@.service.m4.in b/units/container-getty@.service.m4.in
index e126f3a489..fd0be86ba7 100644
--- a/units/container-getty@.service.m4.in
+++ b/units/container-getty@.service.m4.in
@@ -17,7 +17,10 @@ IgnoreOnIsolate=yes
 ConditionPathExists=/dev/pts/%I
 
 [Service]
-ExecStart=-/sbin/agetty --noclear --keep-baud pts/%I 115200,38400,9600 $TERM
+# The '-o' option value tells agetty to replace 'login' arguments with an
+# option to preserve environment (-p), followed by '--' for safety, and then
+# the entered username.
+ExecStart=-/sbin/agetty -o '-p -- \\u' --noclear --keep-baud pts/%I 115200,38400,9600 $TERM
 Type=idle
 Restart=always
 RestartSec=0
diff --git a/units/getty@.service.m4 b/units/getty@.service.m4
index 5b82c13fc5..2a84061ed6 100644
--- a/units/getty@.service.m4
+++ b/units/getty@.service.m4
@@ -33,7 +33,10 @@ ConditionPathExists=/dev/tty0
 
 [Service]
 # the VT is cleared by TTYVTDisallocate
-ExecStart=-/sbin/agetty --noclear %I $TERM
+# The '-o' option value tells agetty to replace 'login' arguments with an
+# option to preserve environment (-p), followed by '--' for safety, and then
+# the entered username.
+ExecStart=-/sbin/agetty -o '-p -- \\u' --noclear %I $TERM
 Type=idle
 Restart=always
 RestartSec=0
diff --git a/units/serial-getty@.service.m4 b/units/serial-getty@.service.m4
index 609c5b62ee..b7caeaff44 100644
--- a/units/serial-getty@.service.m4
+++ b/units/serial-getty@.service.m4
@@ -28,7 +28,10 @@ Conflicts=rescue.service
 Before=rescue.service
 
 [Service]
-ExecStart=-/sbin/agetty --keep-baud 115200,38400,9600 %I $TERM
+# The '-o' option value tells agetty to replace 'login' arguments with an
+# option to preserve environment (-p), followed by '--' for safety, and then
+# the entered username.
+ExecStart=-/sbin/agetty -o '-p -- \\u' --keep-baud 115200,38400,9600 %I $TERM
 Type=idle
 Restart=always
 UtmpIdentifier=%I