diff --git a/xCAT-server/lib/perl/xCAT/IPMI.pm b/xCAT-server/lib/perl/xCAT/IPMI.pm
index a250ff262..c13c01efd 100644
--- a/xCAT-server/lib/perl/xCAT/IPMI.pm
+++ b/xCAT-server/lib/perl/xCAT/IPMI.pm
@@ -44,7 +44,7 @@ use IO::Select;
 #use Data::Dumper;
 use Digest::MD5 qw/md5/;
 my $pendingpackets=0;
-my %tabooseq;
+my %tabooseq; #TODO: this is a global which means one taboo in the whole set causes unrelated session objects to consider it taboo unnecessarily
 my $maxpending; #determined dynamically based on rcvbuf detection
 my $ipmi2support = eval {
     require Digest::SHA1;