怎么快速排查Linux硬件问题

1.快速诊断设备、模块和驱动程序

故障排查的第一步通常是显示Linux服务器上安装的硬件列表。你可以使用ls命令获取硬件的详细信息，比如lspci、lsblk、lscpu和lsscsi。比如说，这是lsblk命令的输出结果：

# lsblkNAME    MAJ:MIN RM SIZE RO TYPE MOUNTPOINTxvda    202:0    0  50G  0 disk├─xvda1 202:1    0   1M  0 part└─xvda2 202:2    0  50G  0 part /xvdb    202:16   0  20G  0 disk└─xvdb1 202:17   0  20G  0 part

如果ls命令没有显示任何错误，使用初始化进程(比如systemd)查看Linux服务器的运行状况。systemd是启动用户空间、控制多个系统进程的最流行的初始化进程。比如说，这是systemctl status命令的输出结果：

# systemctl status● bastion.f347.internal   State: running    Jobs: 0 queued  Failed: 0 units   Since: Wed 2018-11-28 01:29:05 UTC; 2 days ago  CGroup: /          ├─1 /usr/lib/systemd/systemd --switched-root --system --deserialize 21          ├─kubepods.slice          │ ├─kubepods-pod3881728a_f2af_11e8_af77_06af52f87498.slice          │ │ ├─docker-88b27385f4bae77bba834fbd60a61d19026bae13d18eb147783ae27819c34967.scope          │ │ │ └─23860 /opt/bridge/bin/bridge --public-dir=/opt/bridge/static --config=/var/console-config/console-c          │ │ └─docker-a4433f0d523c7e5bc772ee4db1861e4fa56c4e63a2d48f6bc831458c2ce9fd2d.scope          │ │   └─23639 /usr/bin/pod

2.深入研究多个日志

dmesg让你可以搞清楚内核的最新信息中的错误和警示内容。比如说，这是dmesg | more命令的输出结果：

# dmesg | more....[ 1539.027419] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready[ 1539.042726] IPv6: ADDRCONF(NETDEV_UP): veth71f37018: link is not ready[ 1539.048706] IPv6: ADDRCONF(NETDEV_CHANGE): veth71f37018: link becomes ready[ 1539.055034] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready[ 1539.098550] device veth71f37018 entered promiscuous mode[ 1541.450207] device veth71f37018 left promiscuous mode[ 1542.493266] SELinux: mount invalid.  Same superblock, different security settings for (dev mqueue, type mqueue)[ 9965.292788] SELinux: mount invalid.  Same superblock, different security settings for (dev mqueue, type mqueue)[ 9965.449401] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready[ 9965.462738] IPv6: ADDRCONF(NETDEV_UP): vetheacc333c: link is not ready[ 9965.468942] IPv6: ADDRCONF(NETDEV_CHANGE): vetheacc333c: link becomes ready....

你还可以查看/var/log/messages文件中的所有Linux系统日志，在这里找到与特定问题有关的错误。如果你对硬件进行改动，比如挂载额外磁盘或添加以太网网卡，有必要通过tail命令实时密切关注信息。比如说，这是tail -f /var/log/messages命令的输出结果：

# tail -f /var/log/messagesDec  1 13:20:33 bastion dnsmasq[30201]: using nameserver 127.0.0.1#53 for domain in-addr.arpaDec  1 13:20:33 bastion dnsmasq[30201]: using nameserver 127.0.0.1#53 for domain cluster.localDec  1 13:21:03 bastion dnsmasq[30201]: setting upstream servers from DBusDec  1 13:21:03 bastion dnsmasq[30201]: using nameserver 192.199.0.2#53Dec  1 13:21:03 bastion dnsmasq[30201]: using nameserver 127.0.0.1#53 for domain in-addr.arpaDec  1 13:21:03 bastion dnsmasq[30201]: using nameserver 127.0.0.1#53 for domain cluster.localDec  1 13:21:33 bastion dnsmasq[30201]: setting upstream servers from DBusDec  1 13:21:33 bastion dnsmasq[30201]: using nameserver 192.199.0.2#53Dec  1 13:21:33 bastion dnsmasq[30201]: using nameserver 127.0.0.1#53 for domain in-addr.arpaDec  1 13:21:33 bastion dnsmasq[30201]: using nameserver 127.0.0.1#53 for domain cluster.local

3.分析网络功能

你可能在复杂的网络环境中有成千上万个云原生应用程序为业务服务提供服务;这些可能包括虚拟化、多云和混合云。这意味着你应该分析网络连接是否正常运行，这是故障排查的一部分。分析Linux服务器中网络功能的实用命令包括ip addr、traceroute、nslookup、dig和ping等。比如说，这是ip addr show命令的输出结果：

# ip addr show1:lo:  mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000   link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00   inet 127.0.0.1/8 scope host lo      valid_lft forever preferred_lft forever   inet6 ::1/128 scope host      valid_lft forever preferred_lft forever2:eth0:  mtu 9001 qdisc mq state UP group default qlen 1000   link/ether 06:af:52:f8:74:98 brd ff:ff:ff:ff:ff:ff   inet 192.199.0.169/24 brd 192.199.0.255 scope global noprefixroute dynamic eth0      valid_lft 3096sec preferred_lft 3096sec   inet6 fe80::4af:52ff:fef8:7498/64 scope link      valid_lft forever preferred_lft forever3:docker0:  mtu 1500 qdisc noqueue state DOWN group default   link/ether 02:42:67:fb:1a:a2 brd ff:ff:ff:ff:ff:ff   inet 172.17.0.1/16 scope global docker0      valid_lft forever preferred_lft forever   inet6 fe80::42:67ff:fefb:1aa2/64 scope link      valid_lft forever preferred_lft forever....