diff --git a/zconf/lsluns b/zconf/lsluns
index 4d96ebdf..0beea238 100755
--- a/zconf/lsluns
+++ b/zconf/lsluns
@@ -170,6 +170,10 @@ sub get_lun_hash
 sub lsluns_usage {
     print <<EOD;
 Usage:
+This tool is designed for environments where all SCSI devices are attached
+through the zfcp device driver. Expect error messages in mixed environments
+such as with iSCSI.
+
 $PROGRAM_NAME [-c <busid>] ... [-p <wwpn>] ... [-h] [-v]
 
     List LUNs discovered in the Fibre Channel (FC) Storage Area Network (SAN).
diff --git a/zconf/lsluns.8 b/zconf/lsluns.8
index daee0e92..7be5db41 100644
--- a/zconf/lsluns.8
+++ b/zconf/lsluns.8
@@ -4,8 +4,8 @@
 .\"
 .TH LSLUNS 8 "2017-02-17" "s390-tools"
 .SH NAME
-lsluns \- list LUNs discovered in the FC SAN, or show encryption state of
-attached LUNs
+lsluns \- list LUNs discovered in the FC SAN through zfcp, or show encryption state of
+zfcp-attached LUNs
 
 .SH SYNOPSIS
 .B lsluns
@@ -28,6 +28,10 @@ attached LUNs
 
 .SH DESCRIPTION
 .PP
+This tool is designed for environments where all SCSI devices are attached
+through the zfcp device driver. Expect error messages in mixed environments
+such as with iSCSI.
+
 .B lsluns
 lists all logical unit numbers (LUNs) discovered in the
 Fibre Channel (FC) Storage Area Network (SAN).