Sankofa/docs/ceph/PERC_CONTROLLER_CHECK.md

Checking PERC Controller for 250GB Drives

Date: 2025-12-13
Issue: 6x 250GB drives not visible to OS, need to check PERC controller

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Current Status

• OS Detected: Only 2x 300GB drives (sda, sdb)
• Expected: 6x 250GB drives should be visible
• Likely Cause: Drives not configured in PERC controller or in RAID array

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Check PERC Controller

Option 1: Install Dell OpenManage Tools

# Install Dell OpenManage Server Administrator
apt-get update
apt-get install -y srvadmin-all

# Start services
systemctl start dsm_sa_datamgrd
systemctl start dsm_sa_snmpd
systemctl start dsm_sa_eventmgrd

# Check physical disks
omreport storage pdisk controller=0

# Check virtual disks (RAID arrays)
omreport storage vdisk controller=0

Option 2: Use PERC CLI (if available)

# Check if perccli is installed
which perccli

# If not installed, download from Dell
# Then check physical disks
perccli /c0 show

# Check virtual disks
perccli /c0/vall show

Option 3: Check via /proc or /sys

# Check for PERC controller info
cat /proc/scsi/scsi

# Check block devices
ls -la /dev/sd*

# Check for additional controllers
lspci | grep -i raid
lspci | grep -i perc
lspci | grep -i lsi

Option 4: Check dmesg for disk detection

# Check kernel messages for disk detection
dmesg | grep -i "sd[a-z]"
dmesg | grep -i "disk"
dmesg | grep -i "perc"
dmesg | grep -i "raid"

# Check recent disk events
journalctl -k | grep -i disk | tail -50

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What to Look For

If Drives Are in PERC Controller

You should see:

• 8 physical disks total
• 2x 300GB drives (already configured)
• 6x 250GB drives (may be unconfigured or in RAID)

If Drives Are Unconfigured

They may show as:

• "Unconfigured Good" or "Ready"
• Not assigned to any virtual disk
• Available for configuration

If Drives Are in RAID

They may be:

• Part of a RAID array (virtual disk)
• Not exposed as individual disks to OS
• Need to be removed from RAID to use individually

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Next Steps Based on Findings

Scenario 1: Drives Detected in PERC but Unconfigured

Action: Configure drives as individual disks (non-RAID) or create separate virtual disks

# Using perccli (example - adjust for your setup)
# Create individual virtual disks (one per physical disk)
# This exposes each drive to the OS

# Or configure PERC in HBA mode (if supported)
# This passes drives directly to OS without RAID

Scenario 2: Drives Not Detected in PERC

Possible causes:

• Drives not physically installed
• Drive backplane issue
• Controller issue

Action:

1. Check physical installation
2. Check drive bay LEDs
3. Check PERC controller status
4. May need to reseat drives

Scenario 3: Drives in RAID Array

Action:

1. Check RAID configuration
2. Decide if RAID array can be broken up
3. May need to backup data and reconfigure
4. Create individual virtual disks for Ceph OSDs

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Recommended Configuration for Ceph

For Ceph OSDs, you want:

• Individual disks (not in RAID)
• Direct access to each physical disk
• PERC in HBA mode (if supported) or individual virtual disks

Why: Ceph handles redundancy, so RAID is not needed and can reduce performance.

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Quick Check Commands

Run these on R630-01:

# 1. Check for PERC controller
lspci | grep -iE "raid|perc|lsi|megaraid"

# 2. Check kernel messages
dmesg | grep -iE "sd[a-z]|disk|perc" | tail -20

# 3. Check /proc for SCSI devices
cat /proc/scsi/scsi

# 4. Check for additional block devices
lsblk
fdisk -l

# 5. Check if OpenManage is available
which omreport
which perccli

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Summary

The 6x 250GB drives are likely:

1. In PERC controller but not configured/exposed
2. In a RAID array that needs to be reconfigured
3. Not physically installed (less likely if user confirmed they exist)

Next Step: Check PERC controller status to see where the drives are.

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Last Updated: 2025-12-13