我已安装CentOS 7在 中VirtualBox，并希望客户机CentOS使用动态 IP 地址。网络类型为bridged。
主机OS为Windows 7，网络信息如下：
我修改了客户机的网卡配置CentOS：
执行“ service network restart”命令后，使用ip addr显示IP地址：
网络和dhcp相关日志如下：
Jun 4 01:52:40 CentOS kernel: drop_monitor: Initializing network drop monitor service
Jun 4 01:52:40 CentOS kernel: e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k8-NAPI
Jun 4 01:52:41 CentOS kernel: e1000 0000:00:03.0 eth0: Intel(R) PRO/1000 Network Connection
Jun 4 01:52:41 CentOS systemd-udevd[234]: renamed network interface eth0 to enp0s3
Jun 4 01:52:47 CentOS systemd: Starting Import network configuration from initramfs...
Jun 4 01:52:47 CentOS systemd: Started Import network configuration from initramfs.
Jun 4 01:52:51 CentOS systemd: Starting Network Manager...
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> NetworkManager (version 1.0.0-14.git20150121.b4ea599c.el7) is starting...
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> Read config: /etc/NetworkManager/NetworkManager.conf and conf.d: 10-ibft-plugin.conf
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> WEXT support is disabled
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> Acquired D-Bus service com.redhat.ifcfgrh1
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> Loaded plugin ifcfg-rh: (c) 2007 - 2013 Red Hat, Inc. To report bugs please use the NetworkManager mailing list.
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> Loaded plugin iBFT: (c) 2014 Red Hat, Inc. To report bugs please use the NetworkManager mailing list.
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> Loaded plugin keyfile: (c) 2007 - 2013 Red Hat, Inc. To report bugs please use the NetworkManager mailing list.
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> parsing /etc/sysconfig/network-scripts/ifcfg-lo ...
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> parsing /etc/sysconfig/network-scripts/ifcfg-enp0s3 ...
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> read connection 'enp0s3'
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> monitoring kernel firmware directory '/lib/firmware'.
Jun 4 01:52:51 CentOS systemd: Started Network Manager.
Jun 4 01:52:51 CentOS systemd: Starting LSB: Bring up/down networking...
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> WiFi enabled by radio killswitch; enabled by state file
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> WWAN enabled by radio killswitch; enabled by state file
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> WiMAX enabled by radio killswitch; enabled by state file
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> Networking is enabled by state file
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> (lo): link connected
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> (lo): carrier is ON
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> (lo): new Generic device (driver: 'unknown' ifindex: 1)
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> (lo): exported as /org/freedesktop/NetworkManager/Devices/0
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> (enp0s3): carrier is OFF
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> (enp0s3): new Ethernet device (driver: 'e1000' ifindex: 2)
Jun 4 01:52:51 CentOS NetworkManager[689]: <info> (enp0s3): exported as /org/freedesktop/NetworkManager/Devices/1
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): device state change: unmanaged -> unavailable (reason 'managed') [10 20 2]
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): preparing device
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): link connected
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40]
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> Auto-activating connection 'enp0s3'.
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): Activation: starting connection 'enp0s3'
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) scheduled...
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) started...
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> NetworkManager state is now CONNECTING
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) scheduled...
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) complete.
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) starting...
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): device state change: prepare -> config (reason 'none') [40 50 0]
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) successful.
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) complete.
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> parsing /etc/sysconfig/network-scripts/ifcfg-lo ...
Jun 4 01:52:52 CentOS network: Bringing up loopback interface: Could not load file '/etc/sysconfig/network-scripts/ifcfg-lo'
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> parsing /etc/sysconfig/network-scripts/ifcfg-lo ...
Jun 4 01:52:52 CentOS network: Could not load file '/etc/sysconfig/network-scripts/ifcfg-lo'
Jun 4 01:52:52 CentOS NetworkManager[689]: <info> parsing /etc/sysconfig/network-scripts/ifcfg-lo ...
Jun 4 01:52:52 CentOS network: Could not load file '/etc/sysconfig/network-scripts/ifcfg-lo'
Jun 4 01:52:53 CentOS NetworkManager[689]: <info> parsing /etc/sysconfig/network-scripts/ifcfg-lo ...
Jun 4 01:52:53 CentOS network: Could not load file '/etc/sysconfig/network-scripts/ifcfg-lo'
Jun 4 01:52:53 CentOS network: [ OK ]
Jun 4 01:52:53 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) scheduled.
Jun 4 01:52:53 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) started...
Jun 4 01:52:53 CentOS NetworkManager[689]: <info> (enp0s3): device state change: config -> ip-config (reason 'none') [50 70 0]
Jun 4 01:52:53 CentOS NetworkManager[689]: <info> Activation (enp0s3) Beginning DHCPv4 transaction (timeout in 45 seconds)
Jun 4 01:52:53 CentOS NetworkManager[689]: <info> dhclient started with pid 1140
Jun 4 01:52:53 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) complete.
Jun 4 01:52:53 CentOS network: Bringing up interface enp0s3: [ OK ]
Jun 4 01:52:53 CentOS systemd: Started LSB: Bring up/down networking.
Jun 4 01:52:53 CentOS systemd: Starting Network.
Jun 4 01:52:53 CentOS systemd: Reached target Network.
Jun 4 01:52:53 CentOS dhclient[1140]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x623c8c73)
Jun 4 01:52:59 CentOS dhclient[1140]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x623c8c73)
Jun 4 01:53:06 CentOS dhclient[1140]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 7 (xid=0x28b9690d)
Jun 4 01:53:13 CentOS dhclient[1140]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 17 (xid=0x28b9690d)
Jun 4 01:53:24 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) scheduled...
Jun 4 01:53:24 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) started...
Jun 4 01:53:24 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) complete.
Jun 4 01:53:30 CentOS dhclient[1140]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 14 (xid=0x28b9690d)
Jun 4 01:53:38 CentOS NetworkManager[689]: <warn> (enp0s3): DHCPv4 request timed out.
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> (enp0s3): DHCPv4 state changed unknown -> timeout
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> (enp0s3): canceled DHCP transaction, DHCP client pid 1140
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> (enp0s3): DHCPv4 state changed timeout -> done
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) scheduled...
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) started...
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> (enp0s3): device state change: ip-config -> failed (reason 'ip-config-unavailable') [70 120 5]
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> NetworkManager state is now DISCONNECTED
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> startup complete
Jun 4 01:53:38 CentOS NetworkManager[689]: <warn> (enp0s3): Activation: failed for connection 'enp0s3'
Jun 4 01:53:38 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) complete.
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): device state change: failed -> disconnected (reason 'none') [120 30 0]
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): deactivating device (reason 'none') [0]
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> Auto-activating connection 'enp0s3'.
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: starting connection 'enp0s3'
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) scheduled...
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) started...
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> NetworkManager state is now CONNECTING
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) scheduled...
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) complete.
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) starting...
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): device state change: prepare -> config (reason 'none') [40 50 0]
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) successful.
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) complete.
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) scheduled.
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) started...
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): device state change: config -> ip-config (reason 'none') [50 70 0]
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> Activation (enp0s3) Beginning DHCPv4 transaction (timeout in 45 seconds)
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> dhclient started with pid 2365
Jun 4 01:53:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) complete.
Jun 4 01:53:39 CentOS dhclient[2365]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x224ada0f)
Jun 4 01:53:42 CentOS dhclient[2365]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x224ada0f)
Jun 4 01:53:46 CentOS dhclient[2365]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x224ada0f)
Jun 4 01:53:54 CentOS dhclient[2365]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 7 (xid=0x1de75b49)
Jun 4 01:54:01 CentOS dhclient[2365]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 11 (xid=0x1de75b49)
Jun 4 01:54:10 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) scheduled...
Jun 4 01:54:10 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) started...
Jun 4 01:54:10 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) complete.
Jun 4 01:54:12 CentOS dhclient[2365]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 21 (xid=0x1de75b49)
Jun 4 01:54:23 CentOS NetworkManager[689]: <warn> (enp0s3): DHCPv4 request timed out.
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): DHCPv4 state changed unknown -> timeout
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): canceled DHCP transaction, DHCP client pid 2365
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): DHCPv4 state changed timeout -> done
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) scheduled...
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) started...
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): device state change: ip-config -> failed (reason 'ip-config-unavailable') [70 120 5]
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> NetworkManager state is now DISCONNECTED
Jun 4 01:54:23 CentOS NetworkManager[689]: <warn> (enp0s3): Activation: failed for connection 'enp0s3'
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) complete.
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): device state change: failed -> disconnected (reason 'none') [120 30 0]
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): deactivating device (reason 'none') [0]
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> Auto-activating connection 'enp0s3'.
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: starting connection 'enp0s3'
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) scheduled...
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) started...
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> NetworkManager state is now CONNECTING
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) scheduled...
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) complete.
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) starting...
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): device state change: prepare -> config (reason 'none') [40 50 0]
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) successful.
Jun 4 01:54:23 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) complete.
Jun 4 01:54:24 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) scheduled.
Jun 4 01:54:24 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) started...
Jun 4 01:54:24 CentOS NetworkManager[689]: <info> (enp0s3): device state change: config -> ip-config (reason 'none') [50 70 0]
Jun 4 01:54:24 CentOS NetworkManager[689]: <info> Activation (enp0s3) Beginning DHCPv4 transaction (timeout in 45 seconds)
Jun 4 01:54:24 CentOS NetworkManager[689]: <info> dhclient started with pid 2393
Jun 4 01:54:24 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) complete.
Jun 4 01:54:24 CentOS dhclient[2393]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x77843ed1)
Jun 4 01:54:29 CentOS dhclient[2393]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x77843ed1)
Jun 4 01:54:41 CentOS dhclient[2393]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 4 (xid=0xe3a3af6)
Jun 4 01:54:45 CentOS dhclient[2393]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 5 (xid=0xe3a3af6)
Jun 4 01:54:50 CentOS dhclient[2393]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 12 (xid=0xe3a3af6)
Jun 4 01:54:55 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) scheduled...
Jun 4 01:54:55 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) started...
Jun 4 01:54:55 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) complete.
Jun 4 01:55:02 CentOS dhclient[2393]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 14 (xid=0xe3a3af6)
Jun 4 01:55:08 CentOS NetworkManager[689]: <warn> (enp0s3): DHCPv4 request timed out.
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): DHCPv4 state changed unknown -> timeout
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): canceled DHCP transaction, DHCP client pid 2393
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): DHCPv4 state changed timeout -> done
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) scheduled...
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) started...
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): device state change: ip-config -> failed (reason 'ip-config-unavailable') [70 120 5]
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> NetworkManager state is now DISCONNECTED
Jun 4 01:55:08 CentOS NetworkManager[689]: <warn> (enp0s3): Activation: failed for connection 'enp0s3'
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) complete.
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): device state change: failed -> disconnected (reason 'none') [120 30 0]
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): deactivating device (reason 'none') [0]
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> Auto-activating connection 'enp0s3'.
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: starting connection 'enp0s3'
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) scheduled...
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) started...
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> NetworkManager state is now CONNECTING
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) scheduled...
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 1 of 5 (Device Prepare) complete.
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) starting...
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): device state change: prepare -> config (reason 'none') [40 50 0]
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) successful.
Jun 4 01:55:08 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 2 of 5 (Device Configure) complete.
Jun 4 01:55:09 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) scheduled.
Jun 4 01:55:09 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) started...
Jun 4 01:55:09 CentOS NetworkManager[689]: <info> (enp0s3): device state change: config -> ip-config (reason 'none') [50 70 0]
Jun 4 01:55:09 CentOS NetworkManager[689]: <info> Activation (enp0s3) Beginning DHCPv4 transaction (timeout in 45 seconds)
Jun 4 01:55:09 CentOS NetworkManager[689]: <info> dhclient started with pid 2421
Jun 4 01:55:09 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 3 of 5 (IP Configure Start) complete.
Jun 4 01:55:09 CentOS dhclient[2421]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0xc0de211)
Jun 4 01:55:12 CentOS dhclient[2421]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0xc0de211)
Jun 4 01:55:16 CentOS dhclient[2421]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0xc0de211)
Jun 4 01:55:27 CentOS dhclient[2421]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 4 (xid=0x281d5ba3)
Jun 4 01:55:31 CentOS dhclient[2421]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 10 (xid=0x281d5ba3)
Jun 4 01:55:34 CentOS dhclient[2425]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 4 (xid=0x3e3fe85b)
Jun 4 01:55:38 CentOS dhclient[2425]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 5 (xid=0x3e3fe85b)
Jun 4 01:55:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) scheduled...
Jun 4 01:55:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) started...
Jun 4 01:55:39 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv6 Configure Timeout) complete.
Jun 4 01:55:41 CentOS dhclient[2421]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 7 (xid=0x281d5ba3)
Jun 4 01:55:43 CentOS dhclient[2425]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 12 (xid=0x3e3fe85b)
Jun 4 01:55:48 CentOS dhclient[2421]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 11 (xid=0x281d5ba3)
Jun 4 01:55:53 CentOS NetworkManager[689]: <warn> (enp0s3): DHCPv4 request timed out.
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): DHCPv4 state changed unknown -> timeout
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): canceled DHCP transaction, DHCP client pid 2421
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): DHCPv4 state changed timeout -> done
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) scheduled...
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) started...
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): device state change: ip-config -> failed (reason 'ip-config-unavailable') [70 120 5]
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> NetworkManager state is now DISCONNECTED
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> Disabling autoconnect for connection 'enp0s3'.
Jun 4 01:55:53 CentOS NetworkManager[689]: <warn> (enp0s3): Activation: failed for connection 'enp0s3'
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): Activation: Stage 4 of 5 (IPv4 Configure Timeout) complete.
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): device state change: failed -> disconnected (reason 'none') [120 30 0]
Jun 4 01:55:53 CentOS NetworkManager[689]: <info> (enp0s3): deactivating device (reason 'none') [0]
Jun 4 01:55:55 CentOS dhclient[2425]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 11 (xid=0x3e3fe85b)
Jun 4 01:56:06 CentOS dhclient[2425]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 17 (xid=0x3e3fe85b)
Jun 4 01:56:23 CentOS dhclient[2425]: DHCPDISCOVER on enp0s3 to 255.255.255.255 port 67 interval 12 (xid=0x3e3fe85b)
Jun 4 01:56:35 CentOS dhclient[2425]: No DHCPOFFERS received.
Jun 4 01:56:35 CentOS dhclient[2425]: No working leases in persistent database - sleeping.
网卡enp0s3仍然无法获取有效IP地址。有人能就这个问题提供一些线索吗？