Ubuntu服务器/proc/cpuinfo只剩一个处理器问题解决
问题简介
在出差时，遇到了一个比较奇怪的问题，在此记录一下。当时要交付的服务器是Ubuntu 64核，但在系统上架，重新安装部署服务时发现抱错了，因为系统需要至少两个核心才能正常运行。
解决方式
修改完，重启服务器即可。
验证
sqh@sqh-virtual-machine:~$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 60
model name : Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
stepping : 3
microcode : 0x25
cpu MHz : 2501.000
cache size : 6144 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm cpuid_fault epb invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid xsaveopt dtherm ida arat pln pts
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips : 5002.00
clflush size : 64
cache_alignment : 64
address sizes : 42 bits physical, 48 bits virtual
power management:
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 60
model name : Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
stepping : 3
microcode : 0x25
cpu MHz : 2501.000
cache size : 6144 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
apicid : 1
initial apicid : 1
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm cpuid_fault epb invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid xsaveopt dtherm ida arat pln pts
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips : 5002.00
clflush size : 64
cache_alignment : 64
address sizes : 42 bits physical, 48 bits virtual
power management:
processor : 2
vendor_id : GenuineIntel
cpu family : 6
model : 60
model name : Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
stepping : 3
microcode : 0x25
cpu MHz : 2501.000
cache size : 6144 KB
physical id : 1
siblings : 2
core id : 0
cpu cores : 2
apicid : 2
initial apicid : 2
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm cpuid_fault epb invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid xsaveopt dtherm ida arat pln pts
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips : 5002.00
clflush size : 64
cache_alignment : 64
address sizes : 42 bits physical, 48 bits virtual
power management:
processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 60
model name : Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
stepping : 3
microcode : 0x25
cpu MHz : 2501.000
cache size : 6144 KB
physical id : 1
siblings : 2
core id : 1
cpu cores : 2
apicid : 3
initial apicid : 3
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm cpuid_fault epb invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid xsaveopt dtherm ida arat pln pts
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips : 5002.00
clflush size : 64
cache_alignment : 64
address sizes : 42 bits physical, 48 bits virtual
power management:
sqh@sqh-virtual-machine:~$ vim /boot/grub/grub.cfg
sqh@sqh-virtual-machine:~$ vim /boot/grub/grub.cfg
sqh@sqh-virtual-machine:~$ vim /boot/grub/grub.cfg
sqh@sqh-virtual-machine:~$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 60
model name : Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
stepping : 3
microcode : 0x25
cpu MHz : 2501.000
cache size : 6144 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm cpuid_fault epb invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid xsaveopt dtherm ida arat pln pts
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips : 5002.00
clflush size : 64
cache_alignment : 64
address sizes : 42 bits physical, 48 bits virtual
power management:
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 60
model name : Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
stepping : 3
microcode : 0x25
cpu MHz : 2501.000
cache size : 6144 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
apicid : 1
initial apicid : 1
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm cpuid_fault epb invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid xsaveopt dtherm ida arat pln pts
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips : 5002.00
clflush size : 64
cache_alignment : 64
address sizes : 42 bits physical, 48 bits virtual
power management:
processor : 2
vendor_id : GenuineIntel
cpu family : 6
model : 60
model name : Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
stepping : 3
microcode : 0x25
cpu MHz : 2501.000
cache size : 6144 KB
physical id : 1
siblings : 2
core id : 0
cpu cores : 2
apicid : 2
initial apicid : 2
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm cpuid_fault epb invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid xsaveopt dtherm ida arat pln pts
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips : 5002.00
clflush size : 64
cache_alignment : 64
address sizes : 42 bits physical, 48 bits virtual
power management:
processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 60
model name : Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
stepping : 3
microcode : 0x25
cpu MHz : 2501.000
cache size : 6144 KB
physical id : 1
siblings : 2
core id : 1
cpu cores : 2
apicid : 3
initial apicid : 3
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm cpuid_fault epb invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid xsaveopt dtherm ida arat pln pts
bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips : 5002.00
clflush size : 64
cache_alignment : 64
address sizes : 42 bits physical, 48 bits virtual
power management:
总结
如果突然遇到一个这么问题，估计心里时崩溃的，至于原因，我问过同事，（同事遇到的这个问题，同事也没回答出来个123），可能是因为去的路上太过颠簸，导致服务器自动采用了某种安全机制。仅仅记录一下，希望能帮助遇到相同场景的人。
2020年5月24日 17点56分于奥克斯·时代未来之城