diff --git a/xCAT-server/share/xcat/install/ubuntu/service.subiquity.tmpl b/xCAT-server/share/xcat/install/ubuntu/service.subiquity.tmpl
new file mode 100644
index 000000000..ffd5b545d
--- /dev/null
+++ b/xCAT-server/share/xcat/install/ubuntu/service.subiquity.tmpl
@@ -0,0 +1,137 @@
+#cloud-config
+autoinstall:
+  version: 1
+  keyboard: {layout: us, toggle: null, variant: ''}
+  locale: en_US
+  network:
+    version: 2
+    ethernets:
+      xcat-install:
+        match:
+          name: "e*"
+        dhcp4: true
+  ssh:
+    allow-pw: true
+    authorized-keys: []
+    install-server: true
+  identity:
+    realname: 'xCAT Admin'
+    username: xcatadm
+    hostname: #HOSTNAME#
+    password: "#CRYPTORLOCKED:passwd:key=system,username=root:password#"
+#UBUNTU_SUBIQUITY_APT_CONFIG#
+  kernel:
+    package: linux-generic
+  user-data:
+    hostname: #HOSTNAME#
+    disable_root: false
+    package_update: false
+    package_upgrade: false
+    timezone: #TABLE:site:key=timezone:value#
+    chpasswd:
+      list:
+        - "root:#CRYPTORLOCKED:passwd:key=system,username=root:password#"
+      expire: false
+  packages:
+    - openssh-server
+    - openssh-client
+    - wget
+    - vim
+    - rsync
+    - busybox-static
+    - gawk
+    - bind9-dnsutils
+    - chrony
+    - gpg
+    - #INCLUDE_DEFAULT_PKGLIST_AUTOINSTALL#
+  early-commands:
+    - |
+      exec >/tmp/pre-install.log 2>&1
+      set -eux
+      echo "=== xCAT early-commands ==="
+      echo "=== network ==="
+      ip addr show
+      ip route show
+      echo "=== disk detection ==="
+      wget -T 30 -O /tmp/getinstdisk http://#XCATVAR:XCATMASTER##COLONHTTPPORT#/install/autoinst/getinstdisk
+      test -s /tmp/getinstdisk
+      chmod u+x /tmp/getinstdisk
+      /tmp/getinstdisk
+      echo "=== pre-install script ==="
+      wget -T 30 -O /tmp/pre.sh http://#XCATVAR:XCATMASTER##COLONHTTPPORT#/install/autoinst/#HOSTNAME#.pre
+      test -s /tmp/pre.sh
+      chmod u+x /tmp/pre.sh
+      /tmp/pre.sh
+      echo "=== storage injection ==="
+      test -s /tmp/partitionfile
+      sed -i '/^\.\.\.$/d' /autoinstall.yaml
+      cat /tmp/partitionfile >> /autoinstall.yaml
+      echo "=== DNS setup ==="
+      # glibc's resolver discards a nameserver line naming a host, so writing the xcatmaster
+      # *name* leaves the installer -- and the in-target apt that inherits this file -- with no
+      # DNS. Resolve it here, while the live installer's DHCP resolv.conf still works, and keep
+      # that file when the name does not resolve. A name written back is the case this step
+      # exists to prevent.
+      xcatmaster_host="#TABLE:noderes:$NODE:xcatmaster#"
+      xcatmaster_ip="$(getent ahostsv4 "$xcatmaster_host" | awk '{print $1; exit}')"
+      if [ -n "$xcatmaster_ip" ]; then
+        rm -f /etc/resolv.conf
+        echo "nameserver $xcatmaster_ip" >/etc/resolv.conf
+      else
+        echo "xcat: $xcatmaster_host has no IPv4 address; keeping the resolver DHCP supplied"
+      fi
+      echo "domain #TABLE:site:key=domain:value#" >>/etc/resolv.conf
+      echo "=== early-commands complete ==="
+  late-commands:
+    - mkdir -p /target/var/log/xcat/
+    - '{
+    cat /tmp/pre-install.log >> /target/var/log/xcat/xcat.log;
+    installnic="#SUBIQUITYINSTALLNIC#";
+    installmac="#SUBIQUITYINSTALLMAC#";
+    mkdir -p /target/etc/netplan;
+    if [ -z "${installnic}" ]; then
+        printf ''%s\n'' "network:" "  version: 2" "  ethernets:" "    xcat-install:" "      match:" "        macaddress: \"${installmac}\"" "      dhcp4: true" "      dhcp4-overrides:" "        use-domains: true" >/target/etc/netplan/00-xcat-install.yaml;
+    else
+        printf ''%s\n'' "network:" "  version: 2" "  ethernets:" "    xcat-install:" "      match:" "        macaddress: \"${installmac}\"" "      set-name: ${installnic}" "      dhcp4: true" "      dhcp4-overrides:" "        use-domains: true" >/target/etc/netplan/00-xcat-install.yaml;
+    fi;
+    chmod 600 /target/etc/netplan/00-xcat-install.yaml;
+    printf ''%s\n'' ''#HOSTNAME#'' >/target/etc/hostname;
+    if grep -q ''^127\.0\.1\.1'' /target/etc/hosts; then
+        sed -i ''s/^127\.0\.1\.1.*/127.0.1.1 #HOSTNAME#/'' /target/etc/hosts;
+    else
+        printf ''%s\n'' ''127.0.1.1 #HOSTNAME#'' >>/target/etc/hosts;
+    fi;
+    mkdir -p /target/etc/cloud;
+    touch /target/etc/cloud/cloud-init.disabled;
+    echo "Updating kernel command line...";
+    printf ''%s\n'' ''GRUB_CMDLINE_LINUX="#TABLEBLANKOKAY:bootparams:$NODE:kcmdline#"'' >>/target/etc/default/grub;
+    curtin in-target --target /target update-grub2;
+    echo "Running late_command Installation script...";
+    wget -T 30 http://#XCATVAR:XCATMASTER##COLONHTTPPORT#/install/autoinst/#HOSTNAME#.post;
+    chmod u+x #HOSTNAME#.post;
+    cp ./#HOSTNAME#.post /target/root/post.script;
+    curtin in-target --target /target /root/post.script;
+    } >>/target/var/log/xcat/xcat.log 2>&1'
+    # The installer's sources for the otherpkgs repository and the pkgdir mirrors, and the apt
+    # configuration that kept recommended packages out, served the install; ospkgs and otherpkgs
+    # write their own after the first boot. A separate item, so the status of the post script above
+    # still decides whether the install goes on.
+    - rm -f /target/etc/apt/sources.list.d/xcat-otherpkgs-*.list /target/etc/apt/sources.list.d/xcat-otherpkgs-*.sources /target/etc/apt/sources.list.d/xcat-pkgdir-*.list /target/etc/apt/sources.list.d/xcat-pkgdir-*.sources /target/etc/apt/apt.conf.d/94curtin-config
+    # Flip the node to local-disk boot, or it PXE-loops back into the installer on reboot.
+    # xcatd's install monitor greets with "ready", then answers "next" with "done" and runs
+    # "nodeset <node> next". Require both tokens: another service on that port is not a flipped
+    # node. The monitor listens on site.xcatiport; TABLEBLANKOKAY because an absent key fails a
+    # plain TABLE lookup, and with it the whole template.
+    # Retry, and log a failure rather than reinstall silently. Both reads are bounded: a monitor
+    # that accepts and never answers would block a bare read and hang the install here. A
+    # monitor that died and never came back is #7759.
+    - ['bash', '-c', 'xm=#XCATVAR:XCATMASTER#; port="#TABLEBLANKOKAY:site:key=xcatiport:value#"; [ -n "$port" ] || port=3002; ok=0; for i in 1 2 3 4 5; do if exec 3<>/dev/tcp/$xm/$port; then if read -r -t 10 hello <&3 && [ "$hello" = "ready" ]; then printf "next\n" >&3; if read -r -t 10 ack <&3 && [ "$ack" = "done" ]; then ok=1; fi; fi; exec 3>&- 3<&-; [ "$ok" = 1 ] && break; fi; sleep 5; done; if [ "$ok" != 1 ]; then echo "xcat: FAILED to flip $(hostname) to local-disk boot via $xm:$port; the node will PXE back into the installer" >>/target/var/log/xcat/xcat.log; fi; exit 0']
+  error-commands:
+    # Subiquity waits for every error command to return. "nc -l 8080" waits for a collector, which
+    # an unattended install does not have. Keep the archive on the installer, and print the end of
+    # the curtin log to the console, which the management node records.
+    #
+    # Both destinations are read from the environment so a test can point them at its own
+    # directory. The installer sets neither, so an install writes where it always did.
+    - ['sh', '-c', 'tar -c --ignore-failed-read --transform="s/^/#HOSTNAME#-logs\//" /var/crash /var/log/installer /tmp/pre-install.log /autoinstall.yaml >"${XCAT_ERROR_ARCHIVE:-/run/#HOSTNAME#-logs.tar}" 2>/dev/null; exit 0']
+    - ['sh', '-c', 'tail -n 80 /var/log/installer/curtin-install.log >"${XCAT_ERROR_CONSOLE:-/dev/console}" 2>/dev/null; exit 0']
diff --git a/xCAT-test/unit/ubuntu_service_subiquity_template.t b/xCAT-test/unit/ubuntu_service_subiquity_template.t
new file mode 100644
index 000000000..3922a4ba3
--- /dev/null
+++ b/xCAT-test/unit/ubuntu_service_subiquity_template.t
@@ -0,0 +1,61 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+
+use FindBin;
+use Test::More;
+
+# xCAT decides that an Ubuntu osimage uses the Subiquity installer from the NAME of the template
+# it resolved: xCAT_plugin::debian::using_subiquity matches /subiquity/ in the path. That decision
+# controls the netboot kernel command line. A template whose name does not match it makes xCAT
+# boot the live-server initrd with the debian-installer preseed arguments, without boot=casper and
+# without nfsroot, and the node never finds a live filesystem.
+#
+# The compute profile has compute.subiquity.tmpl. The service profile had only service.tmpl, so an
+# Ubuntu 24.04 service node took the preseed path.
+
+use lib "$FindBin::Bin/../../perl-xCAT";
+use lib "$FindBin::Bin/../../xCAT-server/lib/perl";
+use xCAT::SvrUtils;
+
+my $plugin = "$FindBin::Bin/../../xCAT-server/lib/xcat/plugins/debian.pm";
+plan skip_all => 'debian.pm not found' unless -r $plugin;
+eval { require $plugin; 1 } or plan skip_all => "could not load debian.pm: $@";
+
+my $share = "$FindBin::Bin/../../xCAT-server/share/xcat/install/ubuntu";
+plan skip_all => "$share not found" unless -d $share;
+
+# get_file_name takes genos as its last argument. update_tables_with_templates passes 'subiquity'
+# for every Ubuntu 20.04 and later osimage.
+sub resolved {
+    my ($profile, $osver, $genos) = @_;
+    return xCAT::SvrUtils::get_tmpl_file_name($share, $profile, $osver, 'x86_64', $genos);
+}
+
+for my $profile (qw(compute service)) {
+    my $tmpl = resolved($profile, 'ubuntu24.04', 'subiquity');
+    ok(defined $tmpl && -r $tmpl, "$profile: Ubuntu 24.04 resolves an install template");
+    ok(xCAT_plugin::debian::using_subiquity('ubuntu24.04', $tmpl),
+        "$profile: the Ubuntu 24.04 template xCAT resolved is a Subiquity one");
+}
+
+# Ubuntu 18.04 predates Subiquity and keeps the preseed path. genos stays the os version there.
+for my $profile (qw(compute service)) {
+    my $tmpl = resolved($profile, 'ubuntu18.04', 'ubuntu18.04');
+    ok(defined $tmpl && -r $tmpl, "$profile: Ubuntu 18.04 resolves an install template");
+    ok(!xCAT_plugin::debian::using_subiquity('ubuntu18.04', $tmpl),
+        "$profile: Ubuntu 18.04 keeps the debian-installer template");
+}
+
+# The service template must carry the autoinstall document Subiquity reads. A file named for
+# Subiquity that holds a preseed would satisfy using_subiquity and still not install.
+my $service = resolved('service', 'ubuntu24.04', 'subiquity');
+SKIP: {
+    skip 'no service template resolved', 3 unless defined $service && -r $service;
+    my $text = do { local $/; open my $fh, '<', $service or die "$service: $!"; <$fh> };
+    like($text, qr/^#cloud-config/,  'the service template is a cloud-config document');
+    like($text, qr/^autoinstall:/m,  '... carrying an autoinstall section');
+    unlike($text, qr/^d-i /m,        '... and no debian-installer preseed directives');
+}
+
+done_testing();