fix: fix how-tos path, parameterise probe pod, add entrypoint trace

Address the remaining review findings on PR 9964:

- how-tos: the externally-deployed-DS guide pointed at
  docker/ds/default-scripts/setup, a path no release ships.
- bin/ds-backup.sh: probe the first pod from HOSTS instead of hardcoded
  ds-idrepo-0, so a CTS-only backup run is not aborted by an unrelated
  pod check.
- docker-alpine/ds/docker-entrypoint.sh: trace commands to stderr
  (set -x) to ease init-failure debugging; disable with
  ENTRYPOINT_DEBUG=false.

ref: FORGEOPS-6988, FORGEOPS-6989

Co-Authored-By: Claude Code <noreply@anthropic.com>

Author: lee-baines

bin/ds-backup.sh

@@ -66,12 +66,15 @@ if [ -z "${pods}" ]; then
 fi
 echo "Targeting pods: ${pods[@]}"
 
-echo "Verifying the runtime script directory"
+# Probe the first targeted pod, so a CTS-only HOSTS list is not aborted by an
+# unrelated ds-idrepo-0 check.
+probe_pod="${pods[0]}"
+echo "Verifying the runtime script directory on ${probe_pod}"
 # The probe runs under the pod's /bin/sh, not bash: the Alpine DS image ships
 # busybox ash only.
 SCHEDULE_BACKUP_SCRIPT="/opt/opendj/runtime-scripts/schedule-backup.sh"
-kubectl exec ds-idrepo-0 -- sh -c "test -f ${SCHEDULE_BACKUP_SCRIPT}" || {
-    echo "ERROR: ${SCHEDULE_BACKUP_SCRIPT} not found in ds-idrepo-0"
+kubectl exec "${probe_pod}" -- sh -c "test -f ${SCHEDULE_BACKUP_SCRIPT}" || {
+    echo "ERROR: ${SCHEDULE_BACKUP_SCRIPT} not found in ${probe_pod}"
     exit 1
 }
 

docker-alpine/ds/docker-entrypoint.sh

@@ -52,6 +52,13 @@ set -o pipefail
 # SHELLOPTS is a bash-only variable; busybox ash needs no equivalent.
 cd /opt/opendj
 
+# Trace every command to stderr to ease init-failure debugging; disable with
+# -e ENTRYPOINT_DEBUG=false.
+ENTRYPOINT_DEBUG=${ENTRYPOINT_DEBUG:-true}
+if [ "$ENTRYPOINT_DEBUG" = "true" ]; then
+    set -x
+fi
+
 # Container environment (JVM args, password-file locations, cert dirs,
 # bootstrap replication servers). Mode-aware: see env.sh. The forgeops
 # k8s deployment may override any of these via container env/envFrom.

how-tos/pingds-use-an-externally-deployed-ds-with-a-forgeops-deployment.md

@@ -231,7 +231,7 @@ cd /opt/opendj
 Next step is to copy the PingDS runtime setup scripts from your local `forgeops` repo to your PingDS server.  
 
 For 7.4/7.5 release branches or earlier: 
-`docker/ds/default-scripts/setup`
+`docker/ds/runtime-scripts/ds-idrepo/setup` (7.4/7.5 shipped it as `docker/ds/default-scripts/setup`, removed since)
 
 For 2025.2.1:
 `docker/ds/runtime-scripts/ds-idrepo/setup`