As the title, which log file i should pay attention? I don't use X (use ubuntu in text mode), I have python program which use much memmory . When the system break. The ssh can't connnect, keyboard and monitor also don't response. After restart, no kernel crash file in /var/crash . /var/log/kern.log don't have some useful message . There is one line
[ 2241.261714] EXT4-fs error (device sdb1): ext4_mb_g enerate_buddy:756: group 6072, 1629 clusters in bitmap, 1624 in gd; block bitmap corrupt.
But this is not the time it freeze, because there are messages in kern.log at the same moment.So the questions may not to solve the problem, may be the first is How can I find all the message when it freeze. which file should i pay attention. If it can re happened , what I should do before it crash, (some method to make system log more) , excepte memory test , is there anthoer handware problem can check?
I think i should give up ask the general quetsion, In my syslog there so many log like this
Aug 17 22:25:13 engine- mtp-probe: bus: 2, device: 101 was not an MTP device
Aug 17 22:26:07 engine- kernel: [12238.560872] usb 2-1.3: USB disconnect, device number 101
Aug 17 22:26:08 engine- kernel: [12240.041751] usb 2-1.3: new low-speed USB device number 102 using ehci-pci
Aug 17 22:26:08 engine- kernel: [12240.138035] usb 2-1.3: New USB device found, idVendor=046d, idProduct=c077
Aug 17 22:26:08 engine- kernel: [12240.138037] usb 2-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Aug 17 22:26:08 engine- kernel: [12240.138039] usb 2-1.3: Product: USB Optical Mouse
Aug 17 22:26:08 engine- kernel: [12240.138040] usb 2-1.3: Manufacturer: Logitech
Aug 17 22:26:08 engine- kernel: [12240.140164] input: Logitech USB Optical Mouse as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.3/2-1.3:1.0/input/input235
Aug 17 22:26:08 engine- kernel: [12240.140321] hid-generic 0003:046D:C077.00E0: input,hidraw0: USB HID v1.11 Mouse [Logitech USB Optical Mouse] on usb-0000:00:1d.0-1.3/input0
Aug 17 22:26:08 engine- mtp-probe: checking bus 2, device 102: "/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.3"
Aug 17 22:26:08 engine- mtp-probe: bus: 2, device: 102 was not an MTP device
Aug 17 22:27:02 engine- kernel: [12293.623914] usb 2-1.3: USB disconnect, device number 102
Aug 17 22:27:03 engine- kernel: [12295.104785] usb 2-1.3: new low-speed USB device number 103 using ehci-pci
Aug 17 22:27:03 engine- kernel: [12295.201075] usb 2-1.3: New USB device found, idVendor=046d, idProduct=c077
Aug 17 22:27:03 engine- kernel: [12295.201078] usb 2-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Aug 17 22:27:03 engine- kernel: [12295.201079] usb 2-1.3: Product: USB Optical Mouse
This is strange after the system reboot it don't need always check the usb module ? And I don't touch the machine (like insert a usb or plug the usb).
After remove libmtp, and change usb port still have endless message like
Aug 18 09:28:32 engine- kernel: [ 2005.845393] usb 1-1.1: USB disconnect, device number 6
Aug 18 09:28:34 engine- kernel: [ 2007.324639] usb 1-1.1: new low-speed USB device number 7 using ehci-pci
Aug 18 09:28:34 engine- kernel: [ 2007.421178] usb 1-1.1: New USB device found, idVendor=046d, idProduct=c077
Aug 18 09:28:34 engine- kernel: [ 2007.421180] usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Aug 18 09:28:34 engine- kernel: [ 2007.421181] usb 1-1.1: Product: USB Optical Mouse
Aug 18 09:28:34 engine- kernel: [ 2007.421182] usb 1-1.1: Manufacturer: Logitech
Aug 18 09:28:34 engine- kernel: [ 2007.423287] input: Logitech USB Optical Mouse as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.0/input/input35
Aug 18 09:28:34 engine- kernel: [ 2007.423521] hid-generic 0003:046D:C077.0018: input,hidraw0: USB HID v1.11 Mouse [Logitech USB Optical Mouse] on usb-0000:00:1a.0-1.1/input0
Aug 18 09:29:27 engine- kernel: [ 2060.908432] usb 1-1.1: USB disconnect, device number 7
Aug 18 09:29:29 engine- kernel: [ 2062.387676] usb 1-1.1: new low-speed USB device number 8 using ehci-pci
Aug 18 09:29:29 engine- kernel: [ 2062.484091] usb 1-1.1: New USB device found, idVendor=046d, idProduct=c077
Aug 18 09:29:29 engine- kernel: [ 2062.484093] usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Aug 18 09:29:29 engine- kernel: [ 2062.484094] usb 1-1.1: Product: USB Optical Mouse
Aug 18 09:29:29 engine- kernel: [ 2062.484095] usb 1-1.1: Manufacturer: Logitech
Aug 18 09:29:29 engine- kernel: [ 2062.486085] input: Logitech USB Optical Mouse as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.0/input/input36
Aug 18 09:29:29 engine- kernel: [ 2062.486339] hid-generic 0003:046D:C077.0019: input,hidraw0: USB HID v1.11 Mouse [Logitech USB Optical Mouse] on usb-0000:00:1a.0-1.1/input0
Aug 18 09:29:59 engine- kernel: [ 2092.409613] usb 1-1.1: USB disconnect, device number 8
Aug 18 09:30:00 engine- kernel: [ 2093.690148] usb 1-1.2: USB disconnect, device number 4
update
I also meet a situation: There is a kernel call trace in monitor, keyboard can't response, only can reboot. But after reboot the syslog and kern.log doesn't have the kernel calltrace。
syslogd
to log stuff. In particular, the accepted answer says «Mostly, you'll find messages from low-level system services in that file». – Andrea Lazzarotto Aug 17 '14 at 14:25