Script Manage Services
Hi, I am Denys van Kempen, SAP Partner Engineering, This video is part of a series where we cover
what’s new with SAP HANA Cloud.
In this video, we are going to do some system administration and look at the Manage Services
and the Overall Database Status cards on the SAP HANA cockpit.
This video was recorded in April 2020.
For the latest material on this topic, please check the playlist.
There is also a blog for this video with additional information, so if have a question, check
that out first and feel free to post your comments.
Here we are.
SAP HANA Cockpit, system overview, Overall Database Status.
On this card, or tile if you prefer, in the header, we see the host name, a random alphanumeric
string with domain hanacloud.ondemand.com port 443
Green check box, labelled Running.
Related alerts, if any Usage type
Number of hosts Number of Services
Select the card to open the view: Manage Services In the title bar, we see the database name
H00 this will be same for every HANA Cloud service
Status: Running, and number of hosts On the right side we can reset memory statistics
and go to the alerts view.
Reset Memory Statistics is more of a development or support/troubleshooting feature.
Not something you would have every day.
When trying out different configurations, you can do a reset, to compare the baseline,
for example.
You can set the sort order.
I am using process ID here to sort by startup sequence
You can also select the columns you want displayed.
Default view will show the host, which I have unselected.
It is a long string and we are on a single-host system so this provides no information.
I have moved the SQL port up a bit as well, next to TCP port of the process.
Then there are all sorts of memory counters, HANA is an in-memory database, after all.
if you have enough screen real estate, you might want to add a couple, although typically,
as mentioned, this is mainly for troubleshooting.
Customize as you see fit.
We have six services: daemon, nameserver, and compileserver are shared
Those familiar a bit with the SAP HANA architecture, will recognize with the watch dog service,
the daemon, first to start, so with the lowest process
ID, and the first TCP port.
The role column actually only applies to scale-out or distributed systems, same thing; multiple
hosts, where we have master, slave, and standby roles.
We cannot perform any action on the shared services.
The buttons are disabled and this indicates that we are dealing here with a tenant database
system: H00 is the tenant name.
It also happens to be the system identifier, the SID, but you would need to query the database
for that piece of information.
What we can see is that the instance number is double zero as the TCP ports typically
start with 3 and then the instance number, same for the SQL port of the indexserver.
indexserver, dpserver, diserver are specific to our tenant.
the Stop Service action button is enabled and when we select the row, the Kill Service
link is enabled as well, excuse my UNIX, from the kill command.
Now, when would you want to stop a service?
Uncommon activity Again, troubleshooting, the service may no
longer respond to requests.
In case of the dpserver, which stands for the data provisioning server
this is part of SAP HANA smart data integration (SDI),
restarting is relatively harmless, in particular when the service is idle, no
CPU same for the DI server, from HDI, the HANA
Deployment Infrastructure used to generate runtime database objects out of design-time
development artifacts.
We will add some more information about these services in the video blog post.
Now, the Indexserver is the actual database engine: row store and column store.
Restarting means reloading all database objects, and if this starts to approach a terabyte
of data, this will take some time.
Of course, we the have fast-restart option and some other tricks up our sleeve but in
case of the indexserver, be very careful.
Make sure you know what you are doing.
When you click Stop Service, you will need to confirm this.
Note the remark The service may be automatically restarted
depending on how the daemon is configured.
Now, by default, the daemon, the watchdog is configured to restart any service that
is down but we could disable this for a service and then a stop would be stop.
Let’s continue The tenant database is now running with issues,
with a red circle and the status of dpserver is stopping
I manually refresh the view now as the minimal interval for automatic refresh is 1 minute
which is too long for our purpose here everything will be up and running by that
time, so we won’t notice any difference.
Status has changed to not running, with a link
Go to trace file Now the watchdog kicks in and restarts the
service.
Starting A high priority alert is also generated: we
see this in the header and the service alerts column,
We can select the alert and it will open in the Alerts view.
where we can select it for additional information and follow up actions, we will cover this
in a subsequent video.
and when we select the trace file link, this opens the file in the database explorer for
SAP HANA cockpit; again, we will look into how this all works some other time.
Refresh once more and everything is green again.
Kill Service does the same job, except that we can now generate a crash dump file.
This is for advanced troubleshooting.
You might get the request from SAP Support.
From the Memory column we can access Memory Analysis
CPU opens Performance Monitor It does not really matter which row you click,
they all open the same view.
At least, time or recording.
The current status: Running with issues is also displayed on the card on System Overview,
But this will clear in a second, if we return to Manage Services, and another refresh, the
box is green and the status is running again.
OK, brief delta with the SAP Cloud Platform, SAP HANA Service, the predecessor of SAP HANA
Cloud.
Same SAP HANA Cockpit System Overview page with the Overall Database Status card.
Select it to open Manage Services This time we get nine services running
Shared are daemon, nameserver, compileserver, and the preprocessor.
This service provides Text Analysis and Text Mining functionality; no longer included with
SAP HANA Cloud.
For the tenant, here also called H00, we have apart from indexserver, diserver, and dpserver,
the docstore, and scriptserver.
Although this depends When we create an SAP HANA Service instance,
we can actually select whether we want the NoSQL JSON DocumentStore included or not,
and the same applies to the script server and the data provisioning server, so here
we are looking at the enterprise plan with all options selected.
The script server is required for AFL, the application function library, for example,
for PAL, predictive analysis library, we talked about that briefly in the video about System
Information and plugins.
But that’s it, that’s the difference.
Let’s also check the delta with on-premise.
SAP HANA, express edition will do.
SAP HANA cockpit for on-premise systems will include a resource directory and there at
a minimum we would have a system database and a tenant.
If we start with the tenant, Same Overall Database Status card
Manage Services is also the same.
HANA express includes the XS Advanced built-in application server runtime services and a
webdispatcher SAP Cloud Platform already provides Cloud
Foundry application services, so we will not see this for HANA Cloud.
If we return Home, open the directory, and connect to the system database.
Same card again, although now we actually have the option to stop the system.
and when we open the card, we also get a Stop System button in the header.
Stopping and starting the SAP HANA cloud instance is done from the SAP Cloud Platform cockpit
as we have seen, not from the HANA cockpit.
So that’s a difference Note that we can now also stop, or restart
rather, any of the shared services.
The SQL port connects to the nameserver as this hosts the system database.
There is no indexserver here.
If we switch to the database explorer and open the statement library, service overview
and run this in the SQL Console, we get the same information as with Manage Services
The SQL script looks a bit complex but we could also just open the M_SERVICES system
monitoring view Note the IS_DATABASE_LOCAL column
FALSE for shared services If we copy the host name and TCP port of the
dpserver and paste that in a ALTER SYSTEM STOP SERVICE
command run it
and then run a SELECT on the view We get the same result as with the Stop Service
action in Manage Service Stopping
Not active Starting
Yes Active, running that is.
HANA is a database.
We can do everything in SQL as well.
We don’t need a cockpit.
Thats’s it.
Thanks for watching.