SAP B1 HANA Installation On DELL R620

[Former Member]

Dear All;

We are in the process of configuring the hardware platform of SUSE Linux for SAP B1 HANA on server Dell R620. In the following diagram SAP asks to configure hard disks with RAID0 setup which has no redundancy (if one hard disk fails we lose all data).

The customer is concerned about the lack of redundancy of virtual drive 2 and 3 (raid 0) in page 11 as shown in the diagram.

Is the above correct for SAP B1 HANA on Dell R620 server.

We would like also to know how much swap size we need to assign, and on which virtual drive.

Best Regards

~Amal Aloun

[Former Member · Accepted solution]

Dear All;

I noticed that HP servers are using only RAID50 which is more safe, and can give also good performance as the following diagram says:

I want to understand why HP is using a different RAID than DELL.

Best Regards

~Amal Aloun

[Former Member · Accepted solution]

Dear All;

I found the solution, and though of sharing it with you.

SAP Note 1944415 "Configuration Guide for Hardware Platforms of SUSE Linux Enterprise Server" explains each server model with the required RAID that needs to be configured on.

The document which I used earlier was released earlier in 2013, but SAP Note 1944415 is released in JAN 2014.

In my case the server I am using is Dell, and SAP recommends using RAID1/ RAID5 which is more secure and safer than RAID0.

In RAID1 and RAID 5 there is redundancy available, and this will save the customer business from any data loose.

Best Regards

~Amal Aloun

[Former Member · Accepted solution]

I'm curious where you saw RAID1. In the note you referenced, 1944415, it still says to use RAID0 on pages 11 and 12. It's also odd that they say there should be 2 virtual containers, both for the hana log, even though you only have one location for the log file. It's also odd that they say to create one container at a time, each in RAID0. Doesn't RAID0 by default require two drives??

[former_member237781 · Accepted solution]

With the DELL RAID controller you can define one physical drive as a HW-RAID0 drive. You cannot pass-through a physical drive unconfigured to the OS, that's why you define a RAID0. The two RAID0 logical drives are automatically combined to one SW-RAID1 device during the SLES installation process. This ensures redundancy and data protection (see example mdadm output below).

The different RAID configurations between HW partners are a result of the recommendations and investigations during the HANA HW certification process for SAP Business One.

# mdadm -D /dev/md0
/dev/md0:
        Version : 1.0
  Creation Time : Thu Jan  2 12:46:02 2014
     Raid Level : raid1
     Array Size : 292420472 (278.87 GiB 299.44 GB)
  Used Dev Size : 292420472 (278.87 GiB 299.44 GB)
   Raid Devices : 2
  Total Devices : 2
    Persistence : Superblock is persistent

  Intent Bitmap : Internal

    Update Time : Thu Jun 12 13:21:45 2014
          State : active
Active Devices : 2
Working Devices : 2
Failed Devices : 0
  Spare Devices : 0

           Name : xxxxxxxx  (local to host xxxxxxxxxx)
           UUID : b1acf086:523b5239:c9f2e06c:28eccc44
         Events : 504

    Number   Major   Minor   RaidDevice State
       0       8       33        0      active sync   /dev/sdc1
       1       8       49        1      active sync   /dev/sdd1

Best Regards,

Henning Sackewitz

SAP LinuxLab

[Former Member · Accepted solution]

Ah that makes sense. I haven't seen anything in the guides that tell me to set up RAID-1 in software RAID so maybe you all should make that clearer.

I set up a server yesterday and decided to do hardware RAID-5 AND hardware RAID-1. Could you provide some insight as to why you recommend RAID-1 to be set up in SUSE rather than the BIOS?

Also, another customer was wanting to use RAID-10 across all 8 drives on their Dell server. Is there any reason you would advise against that? We are still within the guidelines for storage in each partition with the amount of RAM their server has.

[former_member237781 · Accepted solution]

Please do not depart from the documented HW configurations! As indicated before, these were found to meet the HANA KPIs during the HANA HW certification and are also part of the SAP B1 PAM at https://websmp206.sap-ag.de/~sapidb/011000358700001298912012E/B1H_Supported_Hardware.pdf.

Just like the big HANA boxes pre-installed by the HW vendors, the B1 boxes are HANA appliances that should not setup differently from the certified configuration (RAID, partitions, file systems, etc.).

The SW RAID setup (plus partitioning, volume creation, fs formatting etc.) is done automatically by the setup wizard coming with the SUSE image at https://www.suse.com/slesb1hana . Therefore it relies on the predictable HW RAID storage configurations.

As suggested by you, we may point this out clearer in the guides.

Best Regards,

Henning Sackewitz

SAP LinuxLab

[Former Member · Accepted solution]

We had tried the SUSE image at that link initially but it didn't work for us because the key that Dell provided would only be accepted on the stock SUSE Enterprise 11 Server. We tried to get the key issue resolved with them but were unable to so we didn't have that as an option.

[Former Member · Accepted solution]

I'm seeing on the first link you sent it says to use xfs for the filesystem instead of ext3. I've been using ext3 since my first installation. When did that change?

[former_member237781 · Accepted solution]

The initial DELL 620 certification was done on xfs, so to my knowledge it never changed. It should not be an issue if you had used ext3 so far. HANA generally recommends xfs if not explicitly advised differently (https://css.wdf.sap.corp/sap/support/notes/1944799).

Best Regards,

Henning

[former_member237781 · Accepted solution]

According to SUSE, SLESB1HANA is equal to SLES, and any SLES key should work for both. Did you try to resolve this with Dell or SUSE ? You should approach SUSE for a solution.

Best Regards,

Henning

[Former Member · Accepted solution]

We approached SUSE first and they looked into it but ended up saying they do require different keys and said we should contact Dell. Although we did get the original image from here: https://download.suse.com/Download?buildid=XL0RqEykZpc~

I tried the image at the link you sent above in a VM before reverting back to the normal SUSE Enterprise install and entered the key to see if it would take and it gave the same error which is when we used the normal SUSE image.

[peters2 · Accepted solution]

Hi Jonathan,

could you sent me the key in a private email

to peters@suse.com

in order to talk to Dell and our people what is the issue here.

With the key we can look up for what product it is.

A SLES key should always work with SLES independent

how the image or media is created

Thx

Peter