Hi , I just bumped up my System SP2 from SP1 . and on boot the FC-System dissappeared . But with Qlogic SANSURFER I had to just map the luns again and all was back. But the system spews warning messages like the one listed below. System is Dual opteron 248 with qlogic 2312 attached to an IBM T600. ttached scsi generic sg0 at scsi0, channel 0, id 0, lun 0, type 0 scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:1) UNDERRUN status detected 0x15-0x800. scsi(2:255:1) UNDERRUN status detected 0x15-0x800. scsi(2:255:2) UNDERRUN status detected 0x15-0x800. scsi(2:255:2) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:1) UNDERRUN status detected 0x15-0x800. scsi(2:255:1) UNDERRUN status detected 0x15-0x800. scsi(2:255:2) UNDERRUN status detected 0x15-0x800. scsi(2:255:2) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:1) UNDERRUN status detected 0x15-0x800. scsi(2:255:1) UNDERRUN status detected 0x15-0x800. scsi(2:255:2) UNDERRUN status detected 0x15-0x800. scsi(2:255:2) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:0) UNDERRUN status detected 0x15-0x800. scsi(2:255:1) UNDERRUN status detected 0x15-0x800. scsi(2:255:1) UNDERRUN status detected 0x15-0x800. scsi(2:255:2) UNDERRUN status detected 0x15-0x800. scsi(2:255:2) UNDERRUN status detected 0x15-0x800. serio: kseriod exiting tg3: eth0: Link is up at 1000 Mbps, full duplex. tg3: eth0: Flow control is on for TX and on for RX. tg3: eth1: Link is up at 1000 Mbps, full duplex. tg3: eth1: Flow control is on for TX and on for RX. powernow-k8: Found 2 AMD Athlon 64 / Opteron processors (version 1.39.05) powernow-k8: MP systems not supported by PSB BIOS structure powernow-k8: init not cpu 0 eth0: no IPv6 routers present eth1: no IPv6 routers present QLogic Fibre Channel HBA Driver ACPI: PCI interrupt 0000:03:03.0[A] -> GSI 28 (level, low) -> IRQ 28 qla2300 0000:03:03.0: Found an ISP2312, irq 28, iobase 0xffffff0000015000 qla2300 0000:03:03.0: Configuring PCI space... qla2300 0000:03:03.0: Configure NVRAM parameters... qla2300 0000:03:03.0: Verifying loaded RISC code... scsi(3): Alloc Target 0 @ 00000100f727d000 scsi(3): Alloc Target 1 @ 00000100f8b97000 scsi(3): Alloc Target 2 @ 00000100f8f3d000 scsi(3): Alloc Target 3 @ 00000100f8b94000 scsi(3): **** Load RISC code **** qla2300 0000:03:03.0: Waiting for LIP to complete... scsi(3): Asynchronous P2P MODE received. scsi(3): Asynchronous LOOP UP (2 Gbps). qla2300 0000:03:03.0: LOOP UP detected (2 Gbps). scsi(3): Asynchronous PORT UPDATE. qla2300 0000:03:03.0: Topology - (F_Port), Host Loop address 0xffff scsi(3): RFT_ID exiting normally. scsi(3): RFF_ID exiting normally. scsi(3): RNN_ID exiting normally. scsi(3): RSNN_NN exiting normally. scsi(3): GID_PT entry - nn 200400a0b8163ace pn 200400a0b8163acf portid=010000. scsi(3): GID_PT entry - nn 200400a0b8163ace pn 200500a0b8163acf portid=010400. scsi(3): GID_PT entry - nn 200000e08b0ad239 pn 210000e08b0ad239 portid=010900. scsi(3): GID_PT entry - nn 200800a0b81711fa pn 200800a0b81711fb portid=010100. scsi(3): GID_PT entry - nn 200800a0b81711fa pn 200900a0b81711fb portid=010500. scsi(3): device wrap (010500) scsi(3): Assigning target ID=00 @ 00000100f727d000 to loop id=0x0081, port state=0x4, port down retry=24 scsi(3): Alloc Lun 0 @ tgt 0. scsi(3): Assigning target ID=01 @ 00000100f8b97000 to loop id=0x0082, port state=0x4, port down retry=24 scsi(3): Alloc Lun 0 @ tgt 1. scsi(3): Assigning target ID=02 @ 00000100f8f3d000 to loop id=0x0083, port state=0x4, port down retry=24 scsi(3): Alloc Lun 0 @ tgt 2. scsi(3): Alloc Lun 1 @ tgt 2. scsi(3): Alloc Lun 2 @ tgt 2. scsi(3): Assigning target ID=03 @ 00000100f8b94000 to loop id=0x0084, port state=0x4, port down retry=24 scsi(3): Alloc Lun 0 @ tgt 3. scsi(3): Alloc Lun 1 @ tgt 3. scsi(3): Alloc Lun 2 @ tgt 3. DEBUG: detect hba 3 at address = 00000100fb980328 scsi3 : qla2xxx qla2300 0000:03:03.0: QLogic Fibre Channel HBA Driver: 8.00.02 QLogic QLA2340 - ISP2312: PCI-X (133 MHz) @ 0000:03:03.0 hdma+, host#=3, fw=3.03.11 IPX Vendor: IBM Model: 1722-600 Rev: 0520 Type: Unknown ANSI SCSI revision: 03 qla2300 0000:03:03.0: scsi(3:0:0:0): Enabled tagged queuing, queue depth 32. scsi(3): Asynchronous PORT UPDATE ignored. scsi(3): Asynchronous PORT UPDATE ignored. Attached scsi generic sg1 at scsi3, channel 0, id 0, lun 0, type 31 scsi(3:0:0) UNDERRUN status detected 0x15-0x800. Vendor: IBM Model: 1722-600 Rev: 0520 Type: Unknown ANSI SCSI revision: 03 qla2300 0000:03:03.0: scsi(3:0:1:0): Enabled tagged queuing, queue depth 32. Attached scsi generic sg2 at scsi3, channel 0, id 1, lun 0, type 31 scsi(3:1:0) UNDERRUN status detected 0x15-0x800. Vendor: IBM Model: 1722-600 Rev: 0520 Type: Direct-Access ANSI SCSI revision: 03 qla2300 0000:03:03.0: scsi(3:0:2:0): Enabled tagged queuing, queue depth 32. SCSI device sdb: 487545184 512-byte hdwr sectors (249623 MB) scsi(3:2:0) UNDERRUN status detected 0x15-0x800. SCSI device sdb: drive cache: write back sdb: sdb1 Attached scsi disk sdb at scsi3, channel 0, id 2, lun 0 Attached scsi generic sg3 at scsi3, channel 0, id 2, lun 0, type 0 scsi(3:2:0) UNDERRUN status detected 0x15-0x800. Vendor: IBM Model: 1722-600 Rev: 0520 Type: Direct-Access ANSI SCSI revision: 03 qla2300 0000:03:03.0: scsi(3:0:2:1): Enabled tagged queuing, queue depth 32. scsi(3:2:0) UNDERRUN status detected 0x15-0x800. scsi(3:2:0) UNDERRUN status detected 0x15-0x800. SCSI device sdc: 4269799374 512-byte hdwr sectors (2186137 MB) scsi(3:2:1) UNDERRUN status detected 0x15-0x800. SCSI device sdc: drive cache: write back sdc: sdc1 Attached scsi disk sdc at scsi3, channel 0, id 2, lun 1 Attached scsi generic sg4 at scsi3, channel 0, id 2, lun 1, type 0 Vendor: IBM Model: 1722-600 Rev: 0520 Type: Direct-Access ANSI SCSI revision: 03 qla2300 0000:03:03.0: scsi(3:0:2:2): Enabled tagged queuing, queue depth 32. scsi(3:2:0) UNDERRUN status detected 0x15-0x800. scsi(3:2:0) UNDERRUN status detected 0x15-0x800. scsi(3:2:0) UNDERRUN status detected 0x15-0x800. SCSI device sdd: 3527417856 512-byte hdwr sectors (1806038 MB) scsi(3:2:2) UNDERRUN status detected 0x15-0x800. SCSI device sdd: drive cache: write back scsi(3:2:0) UNDERRUN status detected 0x15-0x800. sdd: sdd1 Attached scsi disk sdd at scsi3, channel 0, id 2, lun 2 scsi(3:2:1) UNDERRUN status detected 0x15-0x800. scsi(3:2:1) UNDERRUN status detected 0x15-0x800. Attached scsi generic sg5 at scsi3, channel 0, id 2, lun 2, type 0 Vendor: IBM Model: 1722-600 Rev: 0520 Type: Direct-Access ANSI SCSI revision: 03 qla2300 0000:03:03.0: scsi(3:0:3:0): Enabled tagged queuing, queue depth 32. scsi(3:2:1) UNDERRUN status detected 0x15-0x800. scsi(3:2:1) UNDERRUN status detected 0x15-0x800. scsi(3:2:1) UNDERRUN status detected 0x15-0x800. scsi(3:2:1) UNDERRUN status detected 0x15-0x800. SCSI device sde: 487545184 512-byte hdwr sectors (249623 MB) scsi(3:3:0) UNDERRUN status detected 0x15-0x800. SCSI device sde: drive cache: write back scsi(3:2:2) UNDERRUN status detected 0x15-0x800. scsi(3:2:2) UNDERRUN status detected 0x15-0x800. scsi(3:2:2) UNDERRUN status detected 0x15-0x800. scsi(3:2:2) UNDERRUN status detected 0x15-0x800. scsi(3:2:2) UNDERRUN status detected 0x15-0x800. scsi(3:2:2) UNDERRUN status detected 0x15-0x800. sde: sde1 Attached scsi disk sde at scsi3, channel 0, id 3, lun 0 Attached scsi generic sg6 at scsi3, channel 0, id 3, lun 0, type 0 scsi(3:3:0) UNDERRUN status detected 0x15-0x800. Vendor: IBM Model: 1722-600 Rev: 0520 Type: Direct-Access ANSI SCSI revision: 03 qla2300 0000:03:03.0: scsi(3:0:3:1): Enabled tagged queuing, queue depth 32. SCSI device sdf: 4269799374 512-byte hdwr sectors (2186137 MB) scsi(3:3:1) UNDERRUN status detected 0x15-0x800. SCSI device sdf: drive cache: write back scsi(3:3:0) UNDERRUN status detected 0x15-0x800. scsi(3:3:0) UNDERRUN status detected 0x15-0x800. scsi(3:3:0) UNDERRUN status detected 0x15-0x800. scsi(3:3:0) UNDERRUN status detected 0x15-0x800. scsi(3:3:0) UNDERRUN status detected 0x15-0x800. scsi(3:3:0) UNDERRUN status detected 0x15-0x800. sdf: sdf1 Attached scsi disk sdf at scsi3, channel 0, id 3, lun 1 Attached scsi generic sg7 at scsi3, channel 0, id 3, lun 1, type 0 Vendor: IBM Model: 1722-600 Rev: 0520 Type: Direct-Access ANSI SCSI revision: 03 qla2300 0000:03:03.0: scsi(3:0:3:2): Enabled tagged queuing, queue depth 32. SCSI device sdg: 3527417856 512-byte hdwr sectors (1806038 MB) scsi(3:3:2) UNDERRUN status detected 0x15-0x800. SCSI device sdg: drive cache: write back scsi(3:3:1) UNDERRUN status detected 0x15-0x800. scsi(3:3:1) UNDERRUN status detected 0x15-0x800. scsi(3:3:1) UNDERRUN status detected 0x15-0x800. scsi(3:3:1) UNDERRUN status detected 0x15-0x800. scsi(3:3:1) UNDERRUN status detected 0x15-0x800. scsi(3:3:1) UNDERRUN status detected 0x15-0x800. scsi(3:2:0) UNDERRUN status detected 0x15-0x800. sdg: sdg1 Attached scsi disk sdg at scsi3, channel 0, id 3, lun 2 Attached scsi generic sg8 at scsi3, channel 0, id 3, lun 2, type 0 scsi(3:3:2) UNDERRUN status detected 0x15-0x800. scsi(3:3:2) UNDERRUN status detected 0x15-0x800. scsi(3:3:2) UNDERRUN status detected 0x15-0x800. scsi(3:3:2) UNDERRUN status detected 0x15-0x800. scsi(3:3:2) UNDERRUN status detected 0x15-0x800. scsi(3:3:2) UNDERRUN status detected 0x15-0x800. scsi(3:255:0) UNDERRUN status detected 0x15-0x800. scsi(3:255:0) UNDERRUN status detected 0x15-0x800. scsi(3:255:0) UNDERRUN status detected 0x15-0x800. scsi(3:255:0) UNDERRUN status detected 0x15-0x800. scsi(3:255:0) UNDERRUN status detected 0x15-0x800. scsi(3:2:1) UNDERRUN status detected 0x15-0x800. scsi(3:255:1) UNDERRUN status detected 0x15-0x800. scsi(3:255:1) UNDERRUN status detected 0x15-0x800. scsi(3:2:2) UNDERRUN status detected 0x15-0x800. scsi(3:255:2) UNDERRUN status detected 0x15-0x800. scsi(3:255:2) UNDERRUN status detected 0x15-0x800. scsi(3:255:0) UNDERRUN status detected 0x15-0x800. scsi(3:255:0) UNDERRUN status detected 0x15-0x800. scsi(3:255:0) UNDERRUN status detected 0x15-0x800. scsi(3:255:1) UNDERRUN status detected 0x15-0x800. scsi(3:255:1) UNDERRUN status detected 0x15-0x800. scsi(3:255:2) UNDERRUN status detected 0x15-0x800. scsi(3:255:2) UNDERRUN status detected 0x15-0x800. scsi(3:3:0) UNDERRUN status detected 0x15-0x800. scsi(3:3:1) UNDERRUN status detected 0x15-0x800. scsi(3:3:2) UNDERRUN status detected 0x15-0x800. SGI XFS Quota Management subsystem XFS mounting filesystem dm-0 Ending clean XFS mount for filesystem: dm-0 The system comes up fine with SP1 and the earlier configuration. I had to use SanSurfer once more to reconfigure the system. For some reason The settings are not being retained when switching between SLES 9 and SP2 and same is repeated between SP1 and SP2 though if I switch between SLES 9 and SP1 the system comes up fine and there are no warning messages. any pointers what is causing this yogesh