diff --git a/xCAT-test/unit/ubuntu_subiquity_error_commands.t b/xCAT-test/unit/ubuntu_subiquity_error_commands.t
new file mode 100755
index 000000000..ee89356ef
--- /dev/null
+++ b/xCAT-test/unit/ubuntu_subiquity_error_commands.t
@@ -0,0 +1,68 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+
+use FindBin;
+use File::Temp qw(tempdir);
+use Test::More;
+
+# Subiquity waits for every error command to return before it reports the failure. The template
+# used to offer the installer logs with "nc -l 8080", which waits for a collector that an
+# unattended install never has, so a failed install stopped there: the node answered ping with no
+# disk or network activity for as long as the provisioning timeout allowed, and the reason for the
+# failure stayed on the node. That is how a missing grub-ieee1275 on ppc64el read as a wedged
+# curtin extract.
+#
+# Run the error commands, with the programs that would reach the host or the network replaced, and
+# check that they return and that they write the end of the curtin log where the caller points.
+
+my $tmpl = "$FindBin::Bin/../../xCAT-server/share/xcat/install/ubuntu/compute.subiquity.tmpl";
+plan skip_all => 'compute.subiquity.tmpl not found' unless -r $tmpl;
+
+open(my $fh, '<', $tmpl) or die "open $tmpl: $!";
+my $source = do { local $/; <$fh> };
+close $fh;
+
+my ($block) = $source =~ m{^  error-commands:\n((?:    [-#].*\n)+)}m;
+BAIL_OUT('the template declares no error-commands') unless $block;
+
+# One command per list item. The list form ['sh', '-c', '...'] carries the command in its last
+# element; a plain item is the command itself.
+my @commands;
+foreach my $line (split /\n/, $block) {
+    next unless $line =~ m{^    - (.*)$};
+    my $item = $1;
+    if ($item =~ m{^\['[^']+', '-c', '(.*)'\]$}) { push @commands, $1; }
+    else                                         { push @commands, $item; }
+}
+BAIL_OUT('no error command found in the block') unless @commands;
+
+my $root = tempdir(CLEANUP => 1);
+my $console = "$root/console";
+my $script  = "$root/error-commands.sh";
+
+# nc, tar and tail are shadowed: bash resolves a function ahead of PATH, so the commands run as
+# written while nothing reaches the host or the network. nc waits the way a listener with no
+# collector waits.
+open(my $out, '>', $script) or die "open $script: $!";
+print {$out} "export XCAT_ERROR_CONSOLE='$console'\n";
+print {$out} "nc() { sleep 300; }\n";
+print {$out} "tar() { :; }\n";
+print {$out} "tail() { echo XCAT_CURTIN_LOG_TAIL; }\n";
+foreach my $command (@commands) {
+    ( my $rendered = $command ) =~ s/#HOSTNAME#/testnode/g;
+    # Subiquity runs each error command on its own, so a command that ends in "exit 0" must not
+    # end the others.
+    print {$out} "( $rendered )\n";
+}
+close $out;
+
+my $rc = system('timeout', '10', 'bash', $script);
+my $status = $rc == -1 ? -1 : $rc >> 8;
+isnt( $status, 124, 'the error commands return instead of waiting for someone to collect the logs' );
+
+my $written = '';
+if (open(my $log, '<', $console)) { local $/; $written = <$log>; close $log; }
+like( $written, qr/XCAT_CURTIN_LOG_TAIL/, 'and write the end of the curtin log to the console the installer names' );
+
+done_testing();