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Downloading SAP Download Basket Contents in the Cloud on Linux

Scenario: You’ve made the move to the cloud. You are about to install some SAP software on a new Linux server hosted in the cloud and you just need to get the installation media uploaded.
Except, you don’t want to have to start X-Windows or setup a specific Windows server just to do this.

You have two options to achieve this, you can either:
Upload the files from your local network using SFTP or SCP (maybe you have ExpressRoute or DirectConnect) and have a fast connection.

Why not just download them straight from your SAP download basket into the target server.
What’s the difference between the two? Well, it depends on whether you’ve already got access to the installation media locally, or if you are intending to first download it locally from SAP, then upload it to your cloud hosted server.
This doesn’t make sense to download then re-upload to the cloud.
Therefore, here’s how you can download straight from your SAP download basket.

What you will need:
– A web browser on your local PC.
– A valid SAP S-user account.
– Disk space on a cloud hosted Linux server (I’m going to show you the Linux way).
– The cloud hosted server will need internet access.

Setup Download Basket:
Before we start downloading, you need to cleanup your download basket.
Go to https://launchpad.support.sap.com/#/downloadbasket
Remove everything already in there that is not the items you want to download to the cloud hosted server.
The reason we must do this is because it’s difficult to know which items relate to which files in the download basket (you’ll see in a moment).
Now you can add the specific items you wish to download, into your download basket.
I’ve got two items:

Export Download Basket:
In the download basket click the “Export Links to Text File” button:

This will generate a text document which you can open on your PC called myDownloadBasketFiles.txt.

Open the text file using notepad:

I have 2 lines for the two items in my download basket. I don’t know which is which. I can suppose they are in order, but I don’t really know for sure.
Take the first line and log onto your cloud hosted Linux server as your preferred user.
Ping the softwaredownload.sap.com server using the Linux utility wget to make sure you can see the server.

> wget https://softwaredownloads.sap.com

A successful ping will show a HTTP error 401 and “Authorization failed“:

We have confirmed that our cloud hosted Linux server can see the SAP download server.
Switch to your target download directory (somewhere with disk space):

> cd mydownloadsdirectory

We now call wget again and pass the first item to download:

> wget –http-user=”[your s-user]” –http-password=”[your password]” [the first url] –output-document=1file.SAR

Adjust the command line above to put in your S-user account name and password.
You should also change the last parameter to give your file a name.

We have to guess that it is a SAR file. Once it’s downloaded you can always re-name and test the extraction using “SAPCAR -tvf thefile.SAR”.

The wget utility will save the file in the current directory.
Repeat the same command line, changing the URL and the output document file, for each of the remaining items in the notepad text file of your download basket.

As you can see, using wget will allow you to script the download process so that you could schedule an overnight download of software.

Dynamic SSH X-11 Forwarding on RHEL Linux

Sometimes you need to use an X-client in order to perform certain operations with an SAP system.
An example would be using SUM (if the firewall ports are blocked) or SWPM to perform an installation, or if you’re running an AS Java system, the offline editor (configtool).

If you’re already using PuTTY to get into the remote system via SSH, then you are already part way there.

In this post, I will show you how to dynamically adjust the PuTTY and Linux configuration so that you can use MobaXterm (or any other X-client) to connect into the Linux using X11 (X-Windows).
This is not the same as using the standard method of ticking the X-11 forwarding option, because this option must be ticked prior to establishing the connection into the server.

Instead of exiting from your session and re-connection, you can simply use standard port forwarding to enable your X-client connection over SSL.

Step 1 – Connect into Linux using PuTTY.

You should ideally already be connected into the remote system using SSH and PuTTY (that is the aim of this post).
If you’re not already connected, then open your PuTTY session as normal.

Step 2 – Open X-Client on your PC/virtual server.

Open your X-Client on your local PC. Ideally it will default to display 0.
The “0” simply refers to a subset of a port range. It’s a virtual display.

In our example, we used the free MobaXterm tool to provide X-client capability. Mainly because the tool is free and integrated into one nice binary that can be placed on a USB stick for easy access.

In MobaXterm, hover the mouse over the “X” in to top right frame of the window.
It should be green, and if so, it will display the current IP and display port it has been configured with.

However, you can use any other X-Client tool (XManager, Exceed, X-Ming, WRQ etc).

Step 3 – Adjust Linux SSH configuration.

The Linux SSH configuration may not be setup to enable X11 forwarding.
This is usually performed by the Linux administrator at a global level in the ssh daemon configuration file.
However, it is possible to adjust the config for individual users only.

As your Linux user (in an SAP system this would usually be the <sid>adm user account), enable the X-11 forwarding:

echo “ForwardX11 yes” > $HOME/.ssh/config

The above command simply enables the current user to forward X11 connections over the SSH connection.
It puts this config into a file called “config” within the .ssh directory of the current Linux user’s home directory.

Step 4 – Setup the port forwarding.

Since this tutorial is going to show the setup of X11 dynamically, with an already established SSH connection, from within your already established PuTTY session, select the Windows window menu from the top left of the PuTTY window and select “Change Settings…“:

Expand the “Connection -> SSH -> Tunnels” settings area on the left hand tree menu:
(Notice there is no option to enable or disable the usual X-11 forwarding option)

On the right hand side, now add port 6000 as source and loclahost:6000 as destination, then select “Remote” and click “Add“:

Click Apply:

What is the above doing?
It is telling PuTTY to establish a listening port on the Linux server, listening on port 6000 (the port for display “0.0”).

The port is “remote” because it is remote to the PuTTY session (i.e. not on the computer where you are running PuTTY).

We’re telling PuTTY to only consider IPv4 because we don’t use IPv6 and have no interest in having it listen for an IPv6 connection.

The above setup will have now established a port forward over the SSH port.
If you were to run “netstat -an | grep 6000” on the Linux server, you would see one port in status LISTEN.

Now the port forwarding is established, all we need to do is configure our Linux session to make use of the display setting.

Step 5 – Configure DISPLAY

In your Linux session, set the DISPLAY variable appropriately.
In a C-shell you would use:

> setenv DISPLAY localhost:0.0

In a Bash, Bourne or Korn shell you would use:

$ export DISPLAY=localhost:0.0

From within the Linux session you should now be able to run an X11 application and see the window on your PC/virtual server.
You can use the standard “xeyes” or “xclock” to perform the test, however sometimes on Linux installs these do not get installed.
I’ve found that it’s generally possible to call “firefox” or “totem” to perform an X11 test.

Alternatively, just call your intended SAP X11 application as discussed at the beginning.

That’s it.

Solaris 10 – Asynch I/O on UFS – Not Really

Whilst investigating a performance issue on an Oracle 10.2.0.5 database running on Solaris 10, I had to do a little digging to discover exactly how asynchronous I/O is implemented within Oracle when the database is using the UFS filesystem.

It was not as straightforward as i thought, because I had to start from the beginning and not trust any current Oracle settings. For example, FILESYSTEMIO_OPTIONS was set to “ASYNCH” in the spfile.
This would normally indicate that a DBA has specifically determined that ASYNCH I/O is possible and that they do not want to use DIRECTIO (or concurrent I/O).

Yet, reading the SAP notes, you would think that this is a moot point.
SAP note 830576 “Parameter recommendations for Oracle 10g” v227 clearly states that Oracle 10.2 on Solaris with UFS filesystems, supports asynchronous I/O, so therefore set the FILESYSTEMIO_OPTIONS to “SETALL”.

However, if you have access to “My Oracle Support” you can check Oracle document “SOLARIS: Asynchronous I/O (AIO) on Solaris (SPARC) servers (Doc ID 48769.1)” which explains that, in Solaris with UFS, Oracle does not actually perform asynchronous I/O at the kernel (Solaris) level. Instead, Solaris simulates AIO by performing parallel writes (calls pwrite() ) but to Oracle it still looks and feels like KAIO.
So, the details in the SAP note are not exactly accurate. AIO is not supported in Solaris, but is simulated. Also, the simulation is just issuing more parallel I/O requests.

If your disk sub-system is slow, it’s still going to be slow, but Oracle writes might be slightly faster if you handle/tune for more parallel requests at the storage layer.

Here’s a nice article that explains it really well: https://sunsite.uakom.sk/sunworldonline/swol-07-1998/swol-07-insidesolaris.html

SAP SWPM Checks Windows Virtual Hostname Setup

When you come to use SWPM for the first time to copy a SAP system which has a virtual hostname defined and used, be aware that the SWPM has in-built checks to ensure that the Windows registry is correctly configured according to SAP note 1564275.

If you’ve not fully implemented the note configuration in the Windows registry, even if you’re using the “SAPINST_USE_HOSTNAME=<hostname>” SAPInst.exe parameter, the SWPM will show an error and exit.

My specific setup was missing the DisableStrictNameChecking setting. After adding this into the registry, I was able to launch SWPM.

Network with OEL 5.7 x86_64 install in Hyper-V

When installing Oracle Enterprise Linux 5.7 x86_64 in a Hyper-V 2012 VM, the Linux networking refuses to work with the Hyper-V “Legacy driver” if you have the UEK (unbreakable enterprise kernel) enabled and more than one vCPU.

First, you should always ensure that you add the Hyper-V “Legacy Network driver” to the VM container at the VM creation time to ensure that it will work when you come to install OEL in the VM.

Then, to get around the problem with the networking and vCPUs, disable the UEK kernel and shutdown, then you can add more than one vCPU to the VM.