Moving drives from G8 to G10

[MarkInMN]

Hello, 

I'm trying to move 8 SATA drives from an older DL360 G8 server to a new DL360 G10 server. The OS is RedHat 7.1 and was working fine on the G8. After moving the drives to the new G10 and booting, Smart Array correctly recognizes the two logical volumes:, with the same configuration as the G8 had:

* First volume is set to about 983 GB, using drives 1 and 2, with RAID1. RH is installed here.

* Second volume is set to about 4 TB, using drives 3-7 (drive 8 is the spare), with RAID5. Apps & data are here..

During boot, the SATA controller recognizes the above volumes, status is OK. All the drive status LEDs are green.

However, RH won't boot, it drops into the 'dracut' emergency shell; for some reason it can't mount the second volume. Using ILO the RH 'fstab' file was edited to comment out the second volume:

/dev/mapper/vg_yms-lv_root / ext4 defaults 1 1
UUID=13e9d97c-a51b-4d70-8418-69ecc31ffc12 /boot ext4 defaults 1 2
# /dev/mapper/vg_yms_data-lv_data1 /data1 ext4 defaults 1 2
/dev/mapper/vg_yms-lv_swap swap swap defaults 0 0

. It's now possible to boot the system directly to emergency mode and login using the previous credentials.  

The first volume's data is intact, with all the files showing the correct data. 

Any speculation as to the issue? I've heard that the G10's require RH 7.6 since the HD controller is different than previous models, yet it does boot from the RH volume. Is it possible that my current RH 7.1 only supports RAID1 on the G10s and not RAID5?

Thanks!

Mark

[Torsten.]

Gen8 drives will be unsupported in gen10 servers and the OS will have no drivers for new hardware. This won't work that way.

[MarkInMN]

Thanks for the reply!

The drives themselves are newer HP drives (HP 655710-B21 to be specific) and the server vendor said they would work ok in a G10. 

I have heard from various sources that either: A) The disk drives aren't compatible, or B) That RedHat 7.6 is needed for any G10, or both. 

I'm just confused - obviously! The drives must be ok & supported on a G10, as SmartArray can configure them and sees the correct RAID setup. If the problematic 2nd volume is removed from the RH 'fstab' file RH can boot into emergency mode, with the normal UI and all the data present. 

So I'm thinking that it's a RedHat issue; for some reason it can't see the 2nd logical volume (the 'lvs' scan says it can't find the logical volume "abcde"). Maybe RH 7.1 only supports RAID1 on a G10 and not RAID5, or it only supports 1 logical volume, so an upgrade to RH 7.6 is needed? I'm guessing here of course - it just seems like I'm one or two configuration steps away from having it work but I've no clue what they might be.

Sorry for being a noob here! This server is an engineering-department system, not part of the corporate IT structure. I'm one of the engineers in the group and I've "inherited" management of this system. Lucky me that the old G8 server suffered a motherboard fault not long after I took over, requiring a replacement server - so here I am! It's been several decades since I was an Unix sysadmin (anyone remember HP-UX?) so I'm trying to clear the cobwebs and remember how the Unix filesystems & volumes all work; so far the spiders are winning.

Thanks, 

Mark

[KM26]

Hello, 

Good day!

We understand the server in question here is a DL360 Gen10. 

In order to check if RHEL version 7.1 is supported on the server, please use the link given below.

https://techlibrary.hpe.com/us/en/enterprise/servers/supportmatrix/redhat_linux.aspx

The supported versions of operating systems also depends on the processors installed on the server. 

Pleaser refer to page 13 of the server quickspecs (link given below) to confirm the details. 

HPE ProLiant DL360 Gen10 Server

https://h20195.www2.hpe.com/v2/getdocument.aspx?docname=a00008159enw#

It is also to be noted that the Gen8 servers and Gen10 servers have different controllers, hence the controller drivers will also differ. 

Since you are trying to boot the server with a pre-installed operating system (the present operating system does not have the Gen10 controller driver), the OS is not booting. 

The likely options for you are to either clean install the OS volume or to look for options with an OS expert to check whether the required driver can be inserted using any method to the existing volume. In the latter option there could still be conflicts with other devices and their drivers in case you are able to fix the boot problem.

If further assistance is required, please log a case with HPE support so that we can help you further.

[MarkInMN · Accepted solution]

Thanks for the reply & links!

Finally decided to update to RHEL 7.7. Even through RH 7.1 was able to boot into emergency mode using the RAID1 volume, the RAID5 volume was just not mountable, tried many different ways.  

With RH 7.7 the system boots clean without using emergency mode, the second volume is now visible so I can at least copy the data off to a backup. Only issue is that I couldn't mount the filesystem using the old name of "/data" - I had to use "/olddata" - However I think that's an application-specific issue, not related to the problems at hand. 

It's been an interesting problem but I think I'm good now. One side benefit was that I did get to re-learn many of the wonders of the Unix filesystem. )

Mark