首先：我对Linux服务器有非常基本的了解。
这里是我们的专用服务器细节：
Intel(R) Xeon(R) CPU X3450 @ 2.67GHz Total processor: 8 OS: Centos 32bit release 5.8 (Final) MySQL version: 5.1.66 PHP version: 5 total used free shared buffers cached Mem: 16413196 16253176 160020 0 79892 12549592 -/+ buffers/cache: 3623692 12789504 Swap: 16386292 0 16386292 Filesystem Size Used Avail /dev/sda1 211G 72G 129G 在过去的两天里，我们遇到了litespeed的问题。 客户在早上给我们打电话，告诉您的网站已closures。 当我检查进程列表litespeed疯狂运行，其CPU使用率为％30 – ％40和PHP进程无法运行意味着我们的网站停机时间。 所以，我重新启动（强制）服务器，它回来后1-2分钟，PHP和litespeed工作正常。
经过对WHM的深入研究，我意识到了这些…
首先，我重新启动服务器后总是收到这封电子邮件：
FAILED: nameserver on ns1.xxx.com (77.223.xxx.xx) nameserver failed @ Fri Dec 28 11:45:59 2012. A restart was attempted automagically. RECOVERED: nameserver on ns1.xxx.com (77.223.xxx.xx) nameserver check was successful after restart.
其次，IO统计对我来说似乎没有什么好处：
Sec Blocks Read/sec Blocks Written/Sec sda 140.51 16327.73 1071.14 55574210
第三，我从日志中得到这个错误：
WARNING: Kernel Errors Present scsi 10:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 11:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 12:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 13:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 14:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 15:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 16:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 17:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 18:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s) scsi 19:0:0:0: scsi: Device offlined - not ready after error recovery ...: 1 Time(s)
（它是这样的）
最后，目前的榜首：
top - 12:46:40 up 1:02, 1 user, load average: 1.26, 1.53, 1.69 Tasks: 165 total, 1 running, 164 sleeping, 0 stopped, 0 zombie Cpu(s): 1.7%us, 0.2%sy, 0.0%ni, 93.6%id, 3.8%wa, 0.0%hi, 0.5%si, 0.0%st Mem: 16413196k total, 16297256k used, 115940k free, 24196k buffers Swap: 16386292k total, 132k used, 16386160k free, 12577056k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 3280 mysql 15 0 10.0g 3.2g 4612 S 13.3 20.2 50:02.38 mysqld 7318 ouruser 15 0 144m 12m 7088 S 1.0 0.1 0:00.03 lsphp5 5137 nobody 0 -19 27628 8000 488 S 0.3 0.0 0:07.53 litespeed 7306 ouruser 15 0 145m 13m 7120 S 0.3 0.1 0:00.29 lsphp5 1 root 15 0 10368 700 584 S 0.0 0.0 0:01.08 init 2 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/0 3 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/0 4 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/0 5 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/1 6 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/1 7 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/1 8 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/2 9 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/2 10 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/2 11 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/3 12 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/3 13 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/3 14 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/4 15 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/4 16 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/4 17 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/5 18 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/5 19 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/5 20 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/6 21 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/6 22 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/6 23 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/7 24 root 34 19 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/7 25 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/7 26 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 events/0 27 root 10 -5 0 0 0 S 0.0 0.0 0:00.02 events/1 28 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 events/2 29 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 events/3 30 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 events/4 31 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 events/5 32 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 events/6 33 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 events/7 34 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 khelper 179 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 kthread 190 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 kblockd/0 191 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 kblockd/1 192 root 10 -5 0 0 0 S 0.0 0.0 0:00.01 kblockd/2 193 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 kblockd/3 194 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 kblockd/4 195 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 kblockd/5 196 root 10 -5 0 0 0 S 0.0 0.0 0:00.02 kblockd/6 197 root 10 -5 0 0 0 S 0.0 0.0 0:00.00 kblockd/7 198 root 10 -5 0 0 0 S 0.0 0.0 0:00.96 kacpid
而“dmesg”的地位：
input: PC Speaker as /class/input/input0 EDAC MC: Ver: 2.0.1 Apr 12 2011 shpchp: Standard Hot Plug PCI Controller Driver version: 0.4 EDAC MC0: Giving out device to i7core_edac.c i7 core #0: DEV 0000:ff:03.0 EDAC i7core: Driver loaded. e1000e: Intel(R) PRO/1000 Network Driver - 1.2.7-k2 e1000e: Copyright (c) 1999 - 2010 Intel Corporation. GSI 20 sharing vector 0x42 and IRQ 20 ACPI: PCI Interrupt 0000:00:19.0[A] -> GSI 17 (level, low) -> IRQ 66 PCI: Setting latency timer of device 0000:00:19.0 to 64 sd 0:0:0:0: Attached scsi generic sg0 type 0 sd 1:0:0:0: Attached scsi generic sg1 type 0 scsi 4:0:0:0: Attached scsi generic sg2 type 5 eth0: (PCI Express:2.5GB/s:Width x1) 00:22:4d:37:6e:fa eth0: Intel(R) PRO/1000 Network Connection eth0: MAC: 9, PHY: 9, PBA No: 313130-032 GSI 21 sharing vector 0x52 and IRQ 21 ACPI: PCI Interrupt 0000:06:00.0[A] -> GSI 18 (level, low) -> IRQ 82 PCI: Setting latency timer of device 0000:06:00.0 to 64 e1000e 0000:06:00.0: Disabling ASPM L0s eth1: (PCI Express:2.5GB/s:Width x1) 00:22:4d:37:6e:f9 eth1: Intel(R) PRO/1000 Network Connection eth1: MAC: 3, PHY: 8, PBA No: 313132-030 ACPI: PCI Interrupt 0000:00:1f.3[D] -> GSI 20 (level, low) -> IRQ 233 sr0: scsi3-mmc drive: 24x/24x writer dvd-ram cd/rw xa/form2 cdda tray Uniform CD-ROM driver Revision: 3.20 sr 4:0:0:0: Attached scsi CD-ROM sr0 floppy0: no floppy controllers found work still pending lp: driver loaded but no devices found ACPI: AC Adapter [PSD] (on-line) ACPI: Power Button (FF) [PWRF] ACPI: Power Button (CM) [PWRB] ACPI: Mapper loaded dell-wmi: No known WMI GUID found power_meter0: Found ACPI power meter. md: Autodetecting RAID arrays. md: autorun ... md: ... autorun DONE. device-mapper: multipath: version 1.0.6 loaded EXT3 FS on sda1, internal journal Adding 16386292k swap on /dev/sda2. Priority:-1 extents:1 across:16386292k IA-32 Microcode Update Driver: v1.14a <[email protected]> loop: loaded (max 8 devices) kjournald starting. Commit interval 5 seconds EXT3-fs warning: checktime reached, running e2fsck is recommended EXT3 FS on loop0, internal journal ext3_orphan_cleanup: deleting unreferenced inode 96 ext3_orphan_cleanup: deleting unreferenced inode 22 ext3_orphan_cleanup: deleting unreferenced inode 17 ext3_orphan_cleanup: deleting unreferenced inode 16 ext3_orphan_cleanup: deleting unreferenced inode 15 ext3_orphan_cleanup: deleting unreferenced inode 14 ext3_orphan_cleanup: deleting unreferenced inode 13 EXT3-fs: loop0: 7 orphan inodes deleted EXT3-fs: recovery complete. EXT3-fs: mounted filesystem with ordered data mode. ip_tables: (C) 2000-2006 Netfilter Core Team Netfilter messages via NETLINK v0.30. ip_conntrack version 2.4 (8192 buckets, 65536 max) - 304 bytes per conntrack e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None eth0: 10/100 speed: disabling TSO NET: Registered protocol family 10 lo: Disabled Privacy Extensions IPv6 over IPv4 tunneling driver eth0: no IPv6 routers present usb 2-1.5: new full speed USB device using ehci_hcd and address 3 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input1 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input2 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 scsi6 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 3 usb-storage: waiting for device to settle before scanning usb 2-1.6: new high speed USB device using ehci_hcd and address 4 usb 2-1.6: configuration #1 chosen from 1 choice scsi7 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 4 usb-storage: waiting for device to settle before scanning power_meter0: Capping in progress. power_meter0: Found ACPI power meter. usb 2-1.5: reset full speed USB device using ehci_hcd and address 3 usb 2-1.5: device firmware changed scsi 6:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.5: USB disconnect, address 3 usb-storage: device scan complete usb 2-1.5: new full speed USB device using ehci_hcd and address 5 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input3 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input4 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 usb 2-1.6: reset high speed USB device using ehci_hcd and address 4 usb 2-1.6: device firmware changed scsi 7:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.6: USB disconnect, address 4 usb-storage: device scan complete usb 2-1.6: new high speed USB device using ehci_hcd and address 6 usb 2-1.6: config 1 has no interfaces? usb 2-1.6: configuration #1 chosen from 1 choice power_meter0: Found ACPI power meter. usb 2-1.5: USB disconnect, address 5 usb 2-1.5: new full speed USB device using ehci_hcd and address 7 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input5 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input6 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 scsi8 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 7 usb-storage: waiting for device to settle before scanning usb 2-1.6: USB disconnect, address 6 usb 2-1.6: new high speed USB device using ehci_hcd and address 8 usb 2-1.6: configuration #1 chosen from 1 choice scsi9 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 8 usb-storage: waiting for device to settle before scanning power_meter0: Capping in progress. power_meter0: Found ACPI power meter. usb 2-1.5: reset full speed USB device using ehci_hcd and address 7 usb 2-1.5: device firmware changed scsi 8:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.5: USB disconnect, address 7 usb-storage: device scan complete usb 2-1.5: new full speed USB device using ehci_hcd and address 9 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input7 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input8 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 usb 2-1.6: reset high speed USB device using ehci_hcd and address 8 usb 2-1.6: device firmware changed scsi 9:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.6: USB disconnect, address 8 usb-storage: device scan complete usb 2-1.6: new high speed USB device using ehci_hcd and address 10 usb 2-1.6: config 1 has no interfaces? usb 2-1.6: configuration #1 chosen from 1 choice power_meter0: Found ACPI power meter. usb 2-1.5: USB disconnect, address 9 usb 2-1.5: new full speed USB device using ehci_hcd and address 11 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input9 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input10 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 scsi10 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 11 usb-storage: waiting for device to settle before scanning usb 2-1.6: USB disconnect, address 10 usb 2-1.6: new high speed USB device using ehci_hcd and address 12 usb 2-1.6: configuration #1 chosen from 1 choice scsi11 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 12 usb-storage: waiting for device to settle before scanning power_meter0: Capping in progress. power_meter0: Found ACPI power meter. usb 2-1.5: reset full speed USB device using ehci_hcd and address 11 usb 2-1.5: device firmware changed scsi 10:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.5: USB disconnect, address 11 usb-storage: device scan complete usb 2-1.5: new full speed USB device using ehci_hcd and address 13 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input11 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input12 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 usb 2-1.6: reset high speed USB device using ehci_hcd and address 12 usb 2-1.6: device firmware changed scsi 11:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.6: USB disconnect, address 12 usb-storage: device scan complete usb 2-1.6: new high speed USB device using ehci_hcd and address 14 usb 2-1.6: config 1 has no interfaces? usb 2-1.6: configuration #1 chosen from 1 choice power_meter0: Found ACPI power meter. usb 2-1.5: USB disconnect, address 13 usb 2-1.5: new full speed USB device using ehci_hcd and address 15 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input13 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input14 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 scsi12 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 15 usb-storage: waiting for device to settle before scanning usb 2-1.6: USB disconnect, address 14 usb 2-1.6: new high speed USB device using ehci_hcd and address 16 usb 2-1.6: configuration #1 chosen from 1 choice scsi13 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 16 usb-storage: waiting for device to settle before scanning power_meter0: Capping in progress. power_meter0: Found ACPI power meter. usb 2-1.5: reset full speed USB device using ehci_hcd and address 15 usb 2-1.5: device firmware changed scsi 12:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.5: USB disconnect, address 15 usb-storage: device scan complete usb 2-1.5: new full speed USB device using ehci_hcd and address 17 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input15 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input16 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 usb 2-1.6: reset high speed USB device using ehci_hcd and address 16 usb 2-1.6: device firmware changed scsi 13:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.6: USB disconnect, address 16 usb-storage: device scan complete usb 2-1.6: new high speed USB device using ehci_hcd and address 18 usb 2-1.6: config 1 has no interfaces? usb 2-1.6: configuration #1 chosen from 1 choice power_meter0: Found ACPI power meter. usb 2-1.5: USB disconnect, address 17 usb 2-1.5: new full speed USB device using ehci_hcd and address 19 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input17 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input18 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 scsi14 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 19 usb-storage: waiting for device to settle before scanning usb 2-1.6: USB disconnect, address 18 usb 2-1.6: new high speed USB device using ehci_hcd and address 20 usb 2-1.6: configuration #1 chosen from 1 choice scsi15 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 20 usb-storage: waiting for device to settle before scanning power_meter0: Capping in progress. power_meter0: Found ACPI power meter. usb 2-1.5: reset full speed USB device using ehci_hcd and address 19 usb 2-1.5: device firmware changed scsi 14:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.5: USB disconnect, address 19 usb-storage: device scan complete usb 2-1.5: new full speed USB device using ehci_hcd and address 21 usb 2-1.5: configuration #1 chosen from 1 choice input: Fujitsu iRMC USB Device as /class/input/input19 input: USB HID v1.11 Keyboard [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 input: Fujitsu iRMC USB Device as /class/input/input20 input: USB HID v1.11 Mouse [Fujitsu iRMC USB Device] on usb-0000:00:1d.0-1.5 usb 2-1.6: reset high speed USB device using ehci_hcd and address 20 usb 2-1.6: device firmware changed scsi 15:0:0:0: scsi: Device offlined - not ready after error recovery usb 2-1.6: USB disconnect, address 20 usb-storage: device scan complete usb 2-1.6: new high speed USB device using ehci_hcd and address 22 usb 2-1.6: config 1 has no interfaces? usb 2-1.6: configuration #1 chosen from 1 choice power_meter0: Found ACPI power meter.
打电话给你的专用服务器提供商，并解释说你有磁盘的麻烦。 显示他们的dmesg输出。 请他们将您移动到新的服务器或更换磁盘。
长期来看，考虑使用某种forms的RAID的专用服务器。
看起来像服务器的iRMC（提供带外键盘，video，鼠标，虚拟CDROM，IPMIpipe理等的硬件）出现故障。 代替它。