diff --git a/xCAT-server/lib/perl/xCAT/Template.pm b/xCAT-server/lib/perl/xCAT/Template.pm
index 547910e78..d02048c88 100644
--- a/xCAT-server/lib/perl/xCAT/Template.pm
+++ b/xCAT-server/lib/perl/xCAT/Template.pm
@@ -47,6 +47,12 @@ my %tab_replacement = (
     "noderes:tftpserver" => "noderes:xcatmaster",
 );
 
+sub httpport_suffix {
+    my $httpport = shift;
+    $httpport = "80" unless defined $httpport and length $httpport;
+    return "" if $httpport eq "80";
+    return ":$httpport";
+}
 
 sub subvars {
     my $self = shift;
@@ -150,7 +156,7 @@ sub subvars {
     }
     $ENV{HTTPPORT} = $httpport;
 
-    $httpportsuffix=":$httpport";
+    $httpportsuffix = httpport_suffix($httpport);
     #replace the env with the right value so that correct include files can be found
     $inc =~ s/#ENV:([^#]+)#/envvar($1)/eg;
     my $res;
@@ -545,7 +551,7 @@ sub subvars {
             }
         }
         elsif ("ubuntu" eq $platform) {
-            my $default_script = "    wget http://`cat /tmp/xcatserver`".':'.$ENV{HTTPPORT} . $ENV{INSTALLDIR} . "/autoinst/getinstdisk; chmod u+x getinstdisk; ./getinstdisk;";
+            my $default_script = "    wget http://`cat /tmp/xcatserver`" . httpport_suffix($ENV{HTTPPORT}) . $ENV{INSTALLDIR} . "/autoinst/getinstdisk; chmod u+x getinstdisk; ./getinstdisk;";
             $inc =~ s/#INCLUDE_GET_INSTALL_DISK_SCRIPT#/$default_script/;
         }
         else {
@@ -1132,7 +1138,7 @@ sub mirrorspec {
                 $pkgdir = $_;
             } else {
                 my $httpport = $ENV{HTTPPORT} || $ENV{httpport} || '80';
-                my $osuurl = "http://" . $masternode . ':' . $httpport . $_ . " ./";
+                my $osuurl = "http://" . $masternode . httpport_suffix($httpport) . $_ . " ./";
                 push @mirrors, $osuurl;
             }
         }
@@ -1141,7 +1147,7 @@ sub mirrorspec {
     if ($pkgdir) {
         my $httpport = $ENV{HTTPPORT} || $ENV{httpport} || '80';
         my $security_host = $masternode;
-        $security_host .= ':' . $httpport if $httpport ne '80';
+        $security_host .= httpport_suffix($httpport);
         $line .= "
 d-i mirror/country string manual\n
 d-i mirror/protocol string http\n
diff --git a/xCAT-test/unit/template_httpport_suffix.t b/xCAT-test/unit/template_httpport_suffix.t
new file mode 100644
index 000000000..0a709937e
--- /dev/null
+++ b/xCAT-test/unit/template_httpport_suffix.t
@@ -0,0 +1,133 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+no warnings 'once';
+
+use FindBin;
+use lib "$FindBin::Bin/../lib";
+use File::Slurper qw(read_text write_text);
+use File::Spec;
+use File::Temp;
+use Test::More;
+
+use XCAT::Test::File qw(repo_path);
+
+my $module = repo_path('xCAT-server/lib/perl/xCAT/Template.pm');
+plan skip_all => 'Template.pm not found' unless -r $module;
+
+my @incs = (
+    repo_path('perl-xCAT'),
+    repo_path('xCAT-server/lib/perl'),
+);
+
+# A mismatched DBI aborts the process instead of dying, so ask a child before
+# loading the module in this process.
+my $devnull = File::Spec->devnull();
+my $probe = join( ' ', $^X, ( map { "-I$_" } @incs ),
+    '-e', "'require xCAT::Template; 1'", ">$devnull", "2>&1" );
+plan skip_all => 'xCAT::Template cannot be loaded here' if system($probe) != 0;
+
+require lib;
+lib->import(@incs);
+require xCAT::Template;
+
+sub suffix { return xCAT::Template::httpport_suffix(@_); }
+
+is( suffix('80'), '', 'the default port gives no suffix' );
+is( suffix('8080'), ':8080', 'another port gives a suffix' );
+is( suffix('443'), ':443', 'the https port gives a suffix' );
+
+# The port is text, as it is in the netboot plugins, so a port that is only
+# equal to 80 as a number keeps the value that the site gave.
+is( suffix('080'), ':080', 'the port is compared as text' );
+
+# site.httpport can be missing, and it can be present but empty.
+is( suffix(undef), '', 'a port that is not set gives no suffix' );
+is( suffix(''),    '', 'a port that is set to nothing gives no suffix' );
+
+my %site;
+no warnings 'redefine', 'once';
+local *xCAT::TableUtils::get_site_attribute = sub {
+    my ( undef, $key ) = @_;
+    return defined $site{$key} ? ( $site{$key} ) : ();
+};
+local *xCAT::NetworkUtils::getipaddr          = sub { return '192.0.2.10'; };
+local *xCAT::Template::getPersistentKcmdline = sub { return ''; };
+use warnings;
+
+my $dir = File::Temp->newdir();
+my $in  = File::Spec->catfile( "$dir", 'in.tmpl' );
+write_text(
+    $in,
+    "url --url http://192.0.2.10#COLONHTTPPORT#/install/pkg\n"
+      . "#INCLUDE_GET_INSTALL_DISK_SCRIPT#\n"
+);
+
+my $render = sub {
+    my ($port) = @_;
+    %site = ( installdir => '/install' );
+    $site{httpport} = $port if defined $port;
+    my $out = File::Spec->catfile( "$dir", "out.${\ ($port || 'default') }" );
+    xCAT::Template->subvars( $in, $out, 'testnode', undef, '/install/pkg',
+        'ubuntu', undef, { xcatmaster => '192.0.2.10' } );
+    return read_text($out);
+};
+
+my $default = $render->(undef);
+like( $default, qr{http://192\.0\.2\.10/install/pkg},
+    'the default port leaves no port in a rendered URL' );
+unlike( $default, qr{:80/}, 'the default port writes no :80' );
+like( $default, qr{wget http://`cat /tmp/xcatserver`/install/autoinst/getinstdisk},
+    'the default getinstdisk URL omits port 80' );
+is( xCAT::Template::ubuntu_subiquity_pkgdir_uri('/install/otherpkgs'),
+    'http://192.0.2.10/install/otherpkgs',
+    'the subiquity URI leaves no port for the default port' );
+
+my $custom = $render->('8080');
+like( $custom, qr{http://192\.0\.2\.10:8080/install/pkg},
+    'another port stays in a rendered URL' );
+like( $custom, qr{wget http://`cat /tmp/xcatserver`:8080/install/autoinst/getinstdisk},
+    'the getinstdisk URL keeps a custom port' );
+is( xCAT::Template::ubuntu_subiquity_pkgdir_uri('/install/otherpkgs'),
+    'http://192.0.2.10:8080/install/otherpkgs',
+    'the subiquity URI keeps another port' );
+is( xCAT::Template::ubuntu_subiquity_pkgdir_uri('http://mirror/pkg'),
+    'http://mirror/pkg', 'a URI that is already whole is left alone' );
+
+{
+    package Local::TemplateNodetype;
+    sub getNodesAttribs {
+        return { testnode => [ { provmethod => 'test-image' } ] };
+    }
+
+    package Local::TemplateLinuximage;
+    sub getAttribs { return { pkgdir => '/install/pkg,/install/other' }; }
+}
+
+no warnings qw(redefine once);
+local *xCAT::Table::new = sub {
+    my ( undef, $name ) = @_;
+    return bless {}, 'Local::TemplateNodetype'  if $name eq 'nodetype';
+    return bless {}, 'Local::TemplateLinuximage' if $name eq 'linuximage';
+    die "Unexpected table $name";
+};
+local *xCAT::TableUtils::get_site_Master = sub { return '192.0.2.10'; };
+{
+    local $ENV{HTTPPORT} = '80';
+    my $mirror = xCAT::Template::mirrorspec();
+    like( $mirror, qr{d-i apt-setup/security_host string 192\.0\.2\.10\n},
+        'the default mirror security host omits port 80' );
+    like( $mirror, qr{deb http://192\.0\.2\.10/install/other \./},
+        'a default-port local mirror omits port 80' );
+}
+
+{
+    local $ENV{HTTPPORT} = '8080';
+    my $mirror = xCAT::Template::mirrorspec();
+    like( $mirror, qr{d-i apt-setup/security_host string 192\.0\.2\.10:8080\n},
+        'the mirror security host keeps a custom port' );
+    like( $mirror, qr{deb http://192\.0\.2\.10:8080/install/other \./},
+        'a local mirror keeps a custom port' );
+}
+
+done_testing();