Fibre Channel on Debian/Ubuntu - Quick Start Guide

sudo apt update
sudo apt install -y multipath-tools sg3-utils sysfsutils
sudo systemctl enable --now multipathd

# Check which FC HBA drivers are loaded
lsmod | grep -E "lpfc|qla2xxx|bnx2fc|bfa"

# If no driver is listed, load the appropriate module for your HBA:
#   Emulex/Broadcom LPe-series: lpfc
#   QLogic QLE-series:          qla2xxx
#   Broadcom NetXtreme FCoE:    bnx2fc
sudo modprobe lpfc       # or qla2xxx / bnx2fc

# Verify HBA ports are online
cat /sys/class/fc_host/host*/port_state
# Expected: Online

# Check link speed (verify cable / SFP negotiated correctly)
cat /sys/class/fc_host/host*/speed
# Example: 16 Gbit

# Discover your WWPNs - register these on the storage array
cat /sys/class/fc_host/host*/port_name
# Example: 0x2100001b32a1bcde

# Option 1: rescan-scsi-bus (preferred - discovers new devices on all host bus adapters)
sudo rescan-scsi-bus.sh

# Option 2: sysfs manual rescan (if rescan-scsi-bus is unavailable)
for host in /sys/class/scsi_host/host*; do
    echo "- - -" | sudo tee "$host/scan"
done

# Verify devices appeared
lsscsi | grep PURE
# Example output:
# [6:0:0:1]  disk  PURE     FlashArray       006.  /dev/sdb

# Confirm multipath picked them up
sudo multipath -ll

sudo tee /etc/multipath.conf > /dev/null <<'EOF'
defaults {
    find_multipaths      no
    polling_interval     10
    path_selector        "service-time 0"
    path_grouping_policy group_by_prio
    failback             immediate
    no_path_retry        0
}

# Blacklist local devices and NVMe to prevent dm-multipath management
# NVMe uses native multipath (nvme_core multipath=Y), not dm-multipath
blacklist {
    # Local boot devices (adjust patterns for your environment)
    devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
    devnode "^sd[a]$"    # Adjust if boot device differs

    # All NVMe devices - use native NVMe multipath instead
    devnode "^nvme"

    # Virtual devices
    devnode "^vd[a-z]"
}

# Add device-specific settings for your storage array
# Default configurations for many storage arrays are included in the multipath package
# Example for a storage array supporting ALUA:
#devices {
#    device {
#        vendor           "VENDOR"
#        product          "PRODUCT"
#        path_selector    "service-time 0"
#        hardware_handler "1 alua"
#        path_grouping_policy group_by_prio
#        prio             alua
#        failback         immediate
#        path_checker     tur
#        fast_io_fail_tmo 5
#        dev_loss_tmo     60
#        no_path_retry    0
#    }
#}
EOF

# Restart multipathd to apply configuration
sudo systemctl restart multipathd

# Verify multipath devices (should only show FC/SAN devices)
sudo multipath -ll

# Find multipath device
sudo multipath -ll
# Example: mpatha -> /dev/mapper/mpatha
# Or by WWID: /dev/mapper/3624a937...

# Create LVM
sudo pvcreate /dev/mapper/mpatha
sudo vgcreate fc-storage /dev/mapper/mpatha
sudo lvcreate -L 500G -n data fc-storage

# Format and mount (Debian/Ubuntu: ext4 recommended)
sudo mkfs.ext4 /dev/fc-storage/data
sudo mkdir -p /mnt/fc-storage
sudo mount /dev/fc-storage/data /mnt/fc-storage

# Add to fstab
echo '/dev/fc-storage/data /mnt/fc-storage ext4 defaults,_netdev 0 0' | sudo tee -a /etc/fstab

# Check HBA port state (all should be Online)
cat /sys/class/fc_host/host*/port_state

# Check multipath paths and ALUA priority groups
sudo multipath -ll

# Verify storage device is visible
lsscsi | grep PURE

# Verify filesystem is mounted (if applicable)
df -h | grep fc-storage