# Sap System Lifecycle > Start, stop and restart a SAP NetWeaver / S/4HANA system in the correct order — database and the instance layer (ERS, ASCS/SCS, PAS, AAS, Web Dispatcher) — using SAPControl (and SAP MMC on Windows) on Linux, Windows and AIX. Use whenever the task is "start/stop/restart the SAP system", "bounce ", "start the app servers", "shut down for maintenance", or ordering the DB relative to the SAP instances. Hands the database start/stop off to sap-db-command-reference. Every command cited to help.sap.com / SAP Notes. - Skill: `williamcorrea23/sap-system-lifecycle` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add williamcorrea23/sap-system-lifecycle` - Raw SKILL.md: https://api.skillmd.com/api/skills/williamcorrea23/sap-system-lifecycle/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Productivity - Author: williamcorrea23 (https://skillmd.com/u/williamcorrea23) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/williamcorrea23/sap-system-lifecycle --- # SAP System Lifecycle (start / stop / restart) `sapcontrol` orchestrates the **SAP instances**; it does **not** start or stop the **database** — the official SAPControl documentation states *"The database is not stopped by these commands. You have to stop the database using database-specific tools or commands."* [V, L1] So a full system operation is always **two layers**: the DB (via [sap-db-command-reference](../sap-db-command-reference/SKILL.md)) and the instances (here). > **`startsap` / `stopsap` are deprecated** — use SAPControl. (SAP Notes 1763593, 809477.) [V, L1] ## Guardrail contract (see repo README) 1. **Identify** — SID, hosts, instance numbers, DB type/OS, and the **topology** (§1) before acting. 2. **Classify** — PRD vs non-PRD; any stop against **PRD** needs an explicit typed confirmation. 3. **Preview** — show the exact command + blast radius. `StopSystem` has no dry-run. 4. **Execute** — via the user's shell/SSH MCP, **one layer/step at a time**, never chained across a stop. 5. **Verify** — `GetProcessList` / `GetSystemInstanceList` after each step (§5). --- ## 1. Identify the topology first List every instance of the system, its host, ports, start priority and status: [G, L4] ```bash # UNIX (host agent copy): /usr/sap/hostctrl/exe/sapcontrol -nr -function GetSystemInstanceList # Windows: %ProgramFiles%\SAP\hostctrl\exe\sapcontrol.exe -nr -function GetSystemInstanceList ``` Output columns: `hostname, instanceNr, httpPort, httpsPort, startPriority, features, dispstatus`. [G, L4] The `features` column tells you the instance type: | `features` contains | Instance | `startPriority` | |---------------------|----------|-----------------| | `ENQREP` | **ERS** — Enqueue Replication Server | **0.5** (first) | | `MESSAGESERVER, ENQUE` (no `ABAP`) | **ASCS** (ABAP) / **SCS** (Java) — Central Services | **1** | | `ABAP, GATEWAY, ICMAN, IGS` (+ `MESSAGESERVER` on the CI) | **PAS / AAS** — application servers | **3** (last) | | `HDB` | database instance (started separately — see DB reference) | — | | Web Dispatcher / standalone GW | front-end / gateway | 3 | --- ## 2. Start order Instances start in **ascending `startPriority`**; the DB must be up before the application servers. [G, L2/L3] ``` 1. DATABASE → via sap-db-command-reference (HDB start / startdb / db2start / …) 2. ERS (prio 0.5) ┐ 3. ASCS/SCS (prio 1) ├─ sapcontrol StartSystem does steps 2–4 in the right order automatically 4. PAS then AAS (prio 3)┘ (ERS is started before ASCS by design) ``` **Operationally (two commands):** ```bash # 1) start the DB first — see sap-db-command-reference for the exact command for your dbms_type # 2) then start all SAP instances of the system in priority order: /usr/sap/hostctrl/exe/sapcontrol -nr -function StartSystem # UNIX [V, L1] ``` ```bat %ProgramFiles%\SAP\hostctrl\exe\sapcontrol.exe -nr -function StartSystem :: Windows ``` - `StartSystem` starts **every** instance of the system in the correct priority sequence. [V, L1] - To start a **single** instance: `sapcontrol -nr -function Start`. [V, L1] - **Remote** instance: add `-host -user `. [V, L1] - **Windows GUI alternative:** the **SAP MMC** (start the system/instance node). [G, L1] --- ## 3. Stop order ⚠️ destructive — no dry-run Reverse of start: application servers first, Central Services last, **then the database**. [G, L2/L3] ``` 1. PAS/AAS (prio 3) ┐ 2. ASCS/SCS (prio 1) ├─ sapcontrol StopSystem does these in reverse-priority order automatically 3. ERS (prio 0.5) ┘ (ASCS is stopped before ERS) 4. DATABASE → via sap-db-command-reference (HDB stop / stopdb / db2stop / …) ``` **Operationally (two commands):** ```bash # 1) stop all SAP instances of the system (reverse priority order): /usr/sap/hostctrl/exe/sapcontrol -nr -function StopSystem # UNIX ⚠️ [V, L1] # 2) then stop the DB — see sap-db-command-reference ``` ```bat %ProgramFiles%\SAP\hostctrl\exe\sapcontrol.exe -nr -function StopSystem :: Windows ``` - Stop a **single** instance: `sapcontrol -nr -function Stop`. [V, L1] - `StopSystem` variants let you scope the stop (e.g. `StopSystem ALL` / dialog instances only); default stops the system's instances in reverse-priority order. Confirm scope before running on PRD. [G, L5] - **Order matters:** never stop the DB before the SAP instances — app servers lose their DB connection ungracefully. Stop instances → verify down → stop DB. --- ## 4. Restart ```bash sapcontrol -nr -function RestartSystem # instances only; DB is untouched [G, L5] ``` For a **full** DB+instance restart, do it as ordered steps, not one command: StopSystem → stop DB → start DB → StartSystem, verifying between each. A restart "for maintenance" usually means: StopSystem → (DB stays up or is stopped per the task) → do the work → StartSystem. --- ## 5. Verify (after every step) ```bash # instances of the whole system + status: sapcontrol -nr -function GetSystemInstanceList # dispstatus GREEN = up [G, L4] # processes of one instance (disp+work, msg server, enqueue, ICM, …): sapcontrol -nr -function GetProcessList # all GREEN [V, L1] ``` `GREEN` = running, `YELLOW` = starting/stopping, `GRAY` = stopped, `RED` = error. Only report a start/stop "done" once the relevant instances show the expected colour. --- ## 6. The control layer (always running) `sapstartsrv` (one per instance) and the **SAP Host Agent** (`saphostexec`, under `/usr/sap/hostctrl/exe`) are the services SAPControl talks to — they run independently of whether the SAP system is up. If `sapcontrol` can't reach an instance, check `sapstartsrv` / the host agent first (`saphostexec -status`), and the boot wiring (§ references). --- ## Cross-references - **Database start/stop commands** (the layer SAPControl doesn't touch): [sap-db-command-reference](../sap-db-command-reference/SKILL.md) — HANA/Oracle/ASE/Db2/MaxDB/SQL Server. - **Is it healthy / first-response triage:** `sap-health-triage`. - **Full `sapcontrol` function catalog, instance-type glossary, and per-OS boot wiring** (systemd / `/etc/inittab` sapinit / Windows services): [references/sapcontrol-and-order.md](references/sapcontrol-and-order.md). ## Run as the correct OS user **Identify the right OS user *before* running anything, and switch with a login shell.** Wrong-user execution is a top cause of SAP failures, and the damage outlives the command: files created by `root` under `/usr/sap`, `/sapmnt` or a DB directory break every later start by the real owner. A login shell also matters because each user carries the environment the tools need (`SAPSYSTEMNAME`, `ORACLE_HOME`/ `ORACLE_SID`, `SYBASE`, `DB2INSTANCE`, library paths) — without it, commands fail or act on the wrong system. | What you're operating | UNIX user | Windows | |---|---|---| | SAP instances — `sapcontrol`, `startsap`/`stopsap`, `tp`, `R3trans`, `disp+work`, `sappfpar`, `cleanipc` | **`adm`** (lower-case **SAP** SID) | `adm`; services run as `SAPService` | | SAP HANA — `HDB`, `hdbsql`, `hdbnsutil` | **`adm` of the HANA SID** (e.g. `h10adm` — may differ from the SAP SID) | n/a (HANA server is Linux-only) | | Oracle — `sqlplus`, `lsnrctl`, BR\*Tools | **`ora`** (BR\*Tools also runs as `adm`; generic installs may use `oracle`) | `adm`; DB runs as a service | | SAP ASE — `isql`, `startserver`, Backup Server | **`syb`** | `syb` / `SAPService` | | IBM Db2 — `db2start`/`db2stop`, `db2` CLP | **`db2`** (the instance owner = `DB2INSTANCE`) | same; Db2 runs as a service | | SAP MaxDB / liveCache — `dbmcli`, `x_server` | **`sdb`** (software owner, group `sdba`) + a DBM operator at DB level | install/service account | | MS SQL Server — `sqlcmd`, service control | n/a (Windows-only for SAP) | `adm` / the SQL Server service account | | SAP Host Agent — `saphostexec`, `saphostctrl` | **`root`** | Administrator / `SAPHostExec` service | **Rules** - **Switch with a login shell:** `su - ` (the `-` is what loads the environment) or `sudo -iu `. Windows: use the correct account, or an elevated shell only where documented. - **`root` only where the procedure explicitly says so** — e.g. `saproot.sh` after a kernel extract, SAP Host Agent install/upgrade. Never as a shortcut around a permission error; that is how root-owned files get created and break the system later. - **Verify before acting:** `whoami` / `id`, plus the env actually being set (`echo $SAPSYSTEMNAME`, `echo $ORACLE_SID`, `echo $DB2INSTANCE`, `echo $SYBASE`). - **State the user in every command you hand over** (e.g. "as `adm`:"), and if the required user is not available, say so and stop — do not substitute another user. ## Staying current — check SAP Notes first SAP Notes supersede this file. Landscapes differ by release, patch level, DB and OS, and SAP changes procedures via Notes/KBAs between doc revisions. **If the [SAP Notes MCP](https://github.com/marianfoo/sap-mcp-servers) is configured, use it before acting on anything version-specific** — especially any destructive step, or when a command here doesn't behave as documented: 1. `search` the topic (e.g. the component + symptom, or a Note number cited below). 2. `fetch` the promising Note IDs for the current text, validity (affected releases/components), prerequisites and side effects. 3. Prefer the Note over this file where they disagree, and say which Note you followed. No MCP available? Look the Note up on `me.sap.com/notes/` and say the check was skipped rather than assuming this file is current. ## Sources - **[L1]** *Starting and Stopping SAP Systems Using SAPControl* — SAP NetWeaver 7.5 / ABAP Platform. **[V]** sapcontrol paths, `StartSystem`/`StopSystem`/`Start`/`Stop`, remote `-host/-user`, `startsap`/`stopsap` deprecated (SAP Notes 1763593, 809477), *"The database is not stopped by these commands."* https://help.sap.com/docs/ABAP_PLATFORM_NEW/30eef4341efd4a2c86f2f98f187eccb3/471d6feeff6e0d46e10000000a155369.html - **[L2]** **SAP Note 897933** — *Start and stop sequence for SAP systems* (canonical sequence + priorities). https://me.sap.com/notes/897933 - **[L3]** Start/stop sequence and `startPriority` (ERS 0.5 → ASCS/SCS 1 → PAS/AAS 3; ERS before ASCS; ASCS stopped before ERS; PAS/AAS require a running DB) — SAP S/4HANA Technical Operation curriculum + Note 897933. [G] - **[L4]** `GetSystemInstanceList` fields (`hostname, instanceNr, httpPort, httpsPort, startPriority, features, dispstatus`) — SAPControl documentation. [G] - **[L5]** *Starting and Stopping SAP System Instances Using Commands* — SAP Help Portal (`RestartSystem`, `StopSystem` scope). https://help.sap.com/docs/PRODUCT_ID/00b4e4853ef3494da20ebcaceb181d5e/0a2f54809e064ee68b02fb9fb392bafd.html **To confirm/deepen** — check current SAP Notes with the SAP Notes MCP (`search`, then `fetch` the note ID): SAP Note 897933 for the exact priority table of your release, and SAP Note 1763593 for the `startsap`/`stopsap` deprecation details.