7 Posts
0
360
August 3rd, 2021 02:00
DellEMC Model: ME4 - Linux not detecting new files on second host upon creation
I have DellEMC ME4 connected to two servers via SAS.
The array is configured using the web interface so that both hosts are in the same group and can see this LUN as a single virtual drive.
When I create a new file on this /dev/sdc1 from host #1, it doesn't show up on host #2 until I umount and mount the drive again (and vice versa).
Anyone noticed something similar and can provide some help?
I'm running debian buster on both hosts and they have 1:1 idendical system (it was cloned).
osowiecki
7 Posts
0
August 4th, 2021 00:00
Ok, I think I misunderstood the protocol used. Connecting 2 servers (hosts) to 1 disk enclosure won't work as there is no communication between servers writing to one virtual volume (LUN 0). I thought the ME4 array would handle both initiators and act like NAS storage. With SAS direct connection it won't.
I think I will split the ME4 volume in two and just give every host access to its exclusive part.
Thank you for your reply.
osowiecki
7 Posts
0
August 3rd, 2021 04:00
rescan-scsi-bus.sh reports it as :
OLD: Host: scsi1 Channel: 00 Id: 03 Lun: 00
Vendor: DellEMC Model: ME4 Rev: G280
Type: Direct-Access ANSI SCSI revision: 06
sg_map detects it correctly as /dev/sdc
/dev/sg2 /dev/sdc
DELL-Charles R
Moderator
•
4.7K Posts
0
August 3rd, 2021 08:00
Hello osowiecki,
Is this a new or existing install?
If existing has anything changed from the time it was working to now?
Check host driver and firmware for HBA, BIOS… are up to date.
Check storage controller firmware GT280R009-02, A08 is up to date : https://www.dell.com/support/home/en-us/product-support/product/powervault-me4012/drivers
Review over best practices for Dell EMC PowerVault ME4 Series storage with Red Hat Enterprise Linux (RHEL).
This section may be helpful page 17- To reclaim LUN 0 for a regular volume
https://downloads.dell.com/manuals/common/powervault-me4-and-linux-best-practices_en-us.pdf