通過(guò)docker-machine +consul +overlay實(shí)現(xiàn)跨主機(jī)通信

一、基礎(chǔ)環(huán)境配置

三臺(tái)服務(wù)器均執(zhí)行以下操作

1. 配置固定IP

[root@localhost ~]#? vim? /etc/sysconfig/network-scripts/ifcfg-ens32

TYPE=Ethernet

PROXY_METHOD=none

BROWSER_ONLY=no

BOOTPROTO=static

DEFROUTE=yes

IPV4_FAILURE_FATAL=no

IPV6INIT=yes

IPV6_AUTOCONF=yes

IPV6_DEFROUTE=yes

IPV6_FAILURE_FATAL=no

IPV6_ADDR_GEN_MODE=stable-privacy

NAME=ens32

UUID=75963e3f-b289-4bbd-8489-44f6f2b8c7f0

DEVICE=ens32

ONBOOT=yes

IPADDR=192.168.0.10

PREFIX=24

GATEWAY=192.168.0.1

DNS1=114.114.114.114

[root@localhost ~]# systemctl restart network

2. 更改主機(jī)名

[root@localhost ~]#? hostnamectl set-hostname docker-ce

[root@localhost ~]#? exit? ? //重新登陸即可

[root@docker-ce ~]#

在20，30兩臺(tái)服務(wù)器上重復(fù)上面的操作，docker1是IPADDR=192.168.0.20，docker2是IPADDR=192.168.0.30

3.關(guān)閉防火墻

[root@docker-ce ~]# systemctl stop firewalld

[root@docker-ce ~]# systemctl disable firewalld

4. 同步系統(tǒng)時(shí)間

[root@docker-ce ~]# yum -y install ntp

[root@docker-ce ~]#? systemctl enable ntpd.service

[root@docker-ce ~]# ntpdate cn.pool.ntp.org

[root@docker-ce ~]# hwclock -w

[root@docker-ce ~]#? crontab -e

0 2 * * * ntpdate ntpdate cn.pool.ntp.org? && hwclock -w

5.關(guān)閉selinux

[root@dockerce ~]# vim /etc/sysconfig/selinux

SELINUX=disabled

[root@docker-ce ~]#? reboot

二、docker-ce配置

1. 安裝docker-machine

方式一：

[root@docker-ce ~]# curl -L https://github.com/docker/machine/releases/download/v0.14.0/docker-machine-`uname -s`-`uname -m` >/tmp/docker-machine && chmod +x /tmp/docker-machine && cp /tmp/docker-machine /usr/local/bin/docker-machine

%Total? ? % Received % Xferd? Average Speed? Time? Time? ? Time? Current

? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Dload? Upload? Total? Spent? ? Left Speed

100? 617? ? 0? 617? 0? ? 0? ? 582? ? 0 --:--:--? 0:00:01 --:--:--? 583

100 25.1M 100 25.1M? ? 0? ? 0? 644k? ? ? 0? 0:00:40 0:00:40 --:--:-- 2801k

此連接安裝時(shí)，有時(shí)會(huì)鏈接超時(shí),多鏈接幾次或是過(guò)會(huì)再鏈接應(yīng)該會(huì)成功。

方式二：

直接下載安裝包

[root@docker-ce ~]# yum -y install wget

[root@docker-ce ~]#? wgethttps://github.com/docker/machine/releases/download/v0.14.0/docker-machine-Linux-x86_64

[root@docker-ce ~]# mv docker-machine-Linux-x86_64 /usr/local/bin/docker-machine

[root@docker-ce ~]# chmod +x? /usr/local/bin/docker-machine

[root@docker-ce ~]# docker-machine version

docker-machine version 0.14.0, build 89b8332

//docker-machine軟件包需要翻墻下載

2. docker1,docker2 配置免密鑰登錄

[root@docker-ce ~]# ssh-keygen? ? //（生成主機(jī)密鑰對(duì)，一路回車即可）

Generating public/private rsa key pair.

Enter file in which to save the key (/root/.ssh/id_rsa):

Created directory '/root/.ssh'.

Enter passphrase (empty for no passphrase):

Enter same passphrase again:

Your identification has been saved in /root/.ssh/id_rsa.

Your public key has been saved in /root/.ssh/id_rsa.pub.

The key fingerprint is:

SHA256:27whAu+mDPZzqj25FcbF47Z8nbIav14KbxGeCl6aZac root@docker-ce

The key's randomart image is:

+---[RSA 2048]----+

|? ? ? ? ? ? ? ? |

|? ? ? .? ? ? ? |

|? ? ? ? +? ? ? ? |

|? ? . o ..? ? ? |

|? ? . + S. o? ? |

|? ? +.++==. .? |

|? o? o+BB+*.+? ? |

| . =+o*.EB.B? ? |

|? ..BO. .+O.? ? |

+----[SHA256]-----+

[root@docker-ce ~]# ssh-copy-id 192.168.0.20? ? //（復(fù)制公鑰到20服務(wù)器）

/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"

The authenticity of host '192.168.0.20 (192.168.0.20)' can't be established.

ECDSA key fingerprint is SHA256:eOpJf2pvOii5sgnKZS+Wb3G3hc/7deEqGzuPcb2Ymhs.

ECDSA key fingerprint is MD5:1f:20:29:32:84:1e:59:cd:47:a5:c9:c3:82:77:50:f6.

Are you sure you want to continue connecting (yes/no)? yes

/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed

/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys

root@192.168.0.20's password:? ? //輸入遠(yuǎn)程主機(jī)20的root用戶的密碼

Number of key(s) added: 1

Now try logging into the machine, with:? "ssh '192.168.0.20'"

and check to make sure that only the key(s) you wanted were added.

[root@docker-ce ~]# ssh-copy-id 192.168.0.30? //（復(fù)制公鑰到30服務(wù)器）

/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"

The authenticity of host '192.168.0.30 (192.168.0.30)' can't be established.

ECDSA key fingerprint is SHA256:eOpJf2pvOii5sgnKZS+Wb3G3hc/7deEqGzuPcb2Ymhs.

ECDSA key fingerprint is MD5:1f:20:29:32:84:1e:59:cd:47:a5:c9:c3:82:77:50:f6.

Are you sure you want to continue connecting (yes/no)? yes

/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed

/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys

root@192.168.0.30's password:? ? //輸入遠(yuǎn)程主機(jī)30的root用戶的密碼

Number of key(s) added: 1

Now try logging into the machine, with:? "ssh '192.168.0.30'"

and check to make sure that only the key(s) you wanted were added.

3. 登陸驗(yàn)證

[root@docker-ce ~]# ssh 192.168.0.20

Last login: Fri May 18 10:42:53 2018 from 192.168.0.110

[root@docker02 ~]# exit

[root@docker-ce ~]# ssh 192.168.0.30

Last login: Fri May 18 10:43:11 2018 from 192.168.0.110

[root@docker03 ~]# exit

4. 批量安裝docker環(huán)境并配置啟動(dòng)

[root@docker-ce ~]# docker-machine ls （查看安裝docker的機(jī)器）

NAME? ACTIVE? DRIVER? STATE? URL? SWARM? DOCKER? ERRORS

在進(jìn)行批量安裝的時(shí)候，主要做以下幾件事：

1> 使用ssh連接到遠(yuǎn)程主機(jī)上（配置無(wú)密碼登錄等原因）

2> 安裝docker（從dockerhub上下載最新的安裝包進(jìn)行安裝）

3> 將本機(jī)生成證書并將證書拷貝到遠(yuǎn)程主機(jī)上

4> 設(shè)置遠(yuǎn)程主機(jī)的啟動(dòng)程序并啟動(dòng)遠(yuǎn)程主機(jī)的docker進(jìn)程

批量安裝時(shí)花費(fèi)的時(shí)間比較長(zhǎng)

[root@docker-ce ~]# docker-machine create -d generic --generic-ip-address=192.168.0.20 docker1（使用generic驅(qū)動(dòng)安裝ip為192.168.0.20的主機(jī)，并且將其主機(jī)名設(shè)置為docker1）

Creating CA: /root/.docker/machine/certs/ca.pem

Creating client certificate: /root/.docker/machine/certs/cert.pem

Running pre-create checks...

Creating machine...

(docker1) No SSH key specified. Assuming an existing key at the default location.

Waiting for machine to be running, this may take a few minutes...

Detecting operating system of created instance...

Waiting for SSH to be available...

Detecting the provisioner...

Provisioning with centos...

Copying certs to the local machine directory...

Copying certs to the remote machine...

Setting Docker configuration on the remote daemon...

Checking connection to Docker...

Docker is up and running!

To see how to connect your Docker Client to the Docker Engine running on this virtual machine, run: docker-machine env docker1

[root@docker-ce ~]# docker-machine create -d generic --generic-ip-address=192.168.0.30 docker2

Running pre-create checks...

Creating machine...

(docker2) No SSH key specified. Assuming an existing key at the default location.

Waiting for machine to be running, this may take a few minutes...

Detecting operating system of created instance...

Waiting for SSH to be available...

Detecting the provisioner...

Provisioning with centos...

Copying certs to the local machine directory...

Copying certs to the remote machine...

Setting Docker configuration on the remote daemon...

Checking connection to Docker...

Docker is up and running!

To see how to connect your Docker Client to the Docker Engine running on this virtual machine, run: docker-machine env docker2

[root@docker-ce ~]# docker-machine ls （檢查是否安裝成功，查看遠(yuǎn)程主機(jī)上的版本）

NAME? ? ? ACTIVE? DRIVER? ? STATE? ? URL? ? ? ? ? ? ? ? ? ? ? SWARM? DOCKER? ? ? ? ERRORS

docker1? -? ? ? ? generic? Running? tcp://192.168.0.20:2376? ? ? ? ? v18.05.0-ce?

docker2? -? ? ? ? generic? Running? tcp://192.168.0.30:2376? ? ? ? ? v18.05.0-ce

5. 其他情況說(shuō)明

在生成證書的時(shí)候，在本機(jī)上和遠(yuǎn)程主機(jī)上都會(huì)保存相關(guān)的證書信息，而且docker-mahine的配置信息也是保存在此位置，相當(dāng)于控制的主機(jī)，如下所示：

[root@docker-ce ~]# ls -l .docker/（在家目錄的隱藏目錄.docker目錄下）

total 4

-rw-------. 1 root root 173 Jan 17 14:52 config.json（保存的是控制機(jī)的配置信息，例如docker客戶端的版本）

drwx------. 4 root root? 35 Jan 13 14:34 machine（保存本機(jī)和遠(yuǎn)程主機(jī)上證書信息及相關(guān)遠(yuǎn)程主機(jī)的配置信息）

遠(yuǎn)程主機(jī)運(yùn)行的進(jìn)程時(shí)候，已經(jīng)做了相關(guān)的配置，進(jìn)程也已經(jīng)啟動(dòng)，查看啟動(dòng)的進(jìn)程信息：

[root@docker2 ~]# ls -l /etc/docker/（證書保存的配置，使用https進(jìn)行通信，保證安全性）

total 20

-rw-r--r--. 1 root root 1029 Jan 20 05:18 ca.pem

-rw-r--r--. 1 root root? 56 Jan 19 03:12 daemon.json

-rw-------. 1 root root? 245 Dec 12 21:40 key.json

-rw-r--r--. 1 root root 1679 Jan 20 05:18 server-key.pem

-rw-r--r--. 1 root root 1103 Jan 20 05:18 server.pem

[root@docker2 ~]# cat /etc/systemd/system/docker.service.d/10-machine.conf

（啟動(dòng)的配置文件，在單機(jī)host環(huán)境中不存在此目錄，此文件會(huì)覆蓋默認(rèn)的啟動(dòng)的配置文件）

[Service]

ExecStart=

ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:2376 -H unix:///var/run/docker.sock --storage-driver devicemapper--tlsverify --tlscacert/etc/docker/ca.pem --tlscert /etc/docker/server.pem --tlskey /etc/docker/server-key.pem --label provider=generic

Environment=

[root@docker2 ~]# ps -ef|grep docker（查看啟動(dòng)的docker進(jìn)程）

root? ? ? 21741? ? ? 1? 0 05:18 ?? ? ? ? 00:00:11 /usr/bin/dockerd -H tcp://0.0.0.0:2376 -H unix:///var/run/docker.sock --storage-driver devicemapper --tlsverify --tlscacert /etc/docker/ca.pem --tlscert /etc/docker/server.pem --tlskey /etc/docker/server-key.pem --label provider=generic

root? ? ? 21746? 21741? 0 05:19 ?? ? ? ? 00:00:11 docker-containerd --config /var/run/docker/containerd/containerd.toml

root? ? ? 21950? 17184? 0 05:39 pts/0? ? 00:00:00 grep --color=auto docker

[root@docker2 ~]# netstat -tunlpx |grep dockerd（查看docker監(jiān)聽的端口）

tcp6? ? ? 0? ? ? 0 :::2376:::*? ? ? ? ? ? ? ? ? ? LISTEN? ? ? 21741/dockerd

unix? 2? ? ? [ ACC ]? ? STREAM? ? LISTENING? ? 324400? 21741/dockerd? ? ? ? /var/run/docker.sock

unix? 2? ? ? [ ACC ]? ? STREAM? ? LISTENING? ? 323509? 21741/dockerd? ? ? ? /var/run/docker/metrics.sock

unix? 2? ? ? [ ACC ]? ? STREAM? ? LISTENING? ? 324567? 21741/dockerd? ? ? ? /run/docker/libnetwork/fc7eb55d830a15800059dcf61156a80314b2ba7354834170cf198702e586f22e.sock

在使用多機(jī)環(huán)境的時(shí)候需要注意的是，啟動(dòng)的配置文件已經(jīng)被覆蓋了，如果去修改單機(jī)環(huán)境中的啟動(dòng)的配置文件是不能生效的，必須要修改新創(chuàng)建的目錄下的文件內(nèi)容。

三、跨主機(jī)通信

使用overlay驅(qū)動(dòng)進(jìn)行跨主機(jī)通信，在使用此驅(qū)動(dòng)的時(shí)候，是通過(guò)udp的4789端口進(jìn)行通信。

1. 創(chuàng)建數(shù)據(jù)庫(kù)來(lái)保存網(wǎng)絡(luò)信息

docker-ce配置

直接使用容器consul來(lái)進(jìn)行運(yùn)行，如下所示：

[root@docker-ce]# docker run -d -p 8500:8500 -h consul --name consul progrium/consul --server -bootstrap

Unable to find image 'progrium/consul:latest' locally

latest: Pulling from progrium/consul

c862d82a67a2: Pull complete

0e7f3c08384e: Pull complete

0e221e32327a: Pull complete

09a952464e47: Pull complete

60a1b927414d: Pull complete

4c9f46b5ccce: Pull complete

417d86672aa4: Pull complete

b0d47ad24447: Pull complete

fd5300bd53f0: Pull complete

a3ed95caeb02: Pull complete

d023b445076e: Pull complete

ba8851f89e33: Pull complete

5d1cefca2a28: Pull complete

Digest: sha256:8cc8023462905929df9a79ff67ee435a36848ce7a10f18d6d0faba9306b97274

Status: Downloaded newer image for progrium/consul:latest

6ac42624732d189e0e8913c69632b266e0fe67103c4f1403ffd8b155cffc1e61

[root@docker-ce]# docker ps

CONTAINER ID? ? ? ? IMAGE? ? ? ? ? ? ? COMMAND? ? ? ? ? ? ? ? ? CREATED? ? ? ? ? ? STATUS? ? ? ? ? ? ? PORTS? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? NAMES

6ac42624732d? ? ? ? progrium/consul? ? "/bin/start --server…"? 18 seconds ago? ? ? Up 14 seconds? ? ? 53/tcp, 53/udp, 8300-8302/tcp, 8400/tcp, 8301-8302/udp, 0.0.0.0:8500->8500/tcp? consul

使用ip加端口直接進(jìn)行訪問(wèn)，此處是http://192.168.0.10:8500

2. 遠(yuǎn)程主機(jī)配置

在遠(yuǎn)程主機(jī)上要在這個(gè)數(shù)據(jù)庫(kù)上注冊(cè)，從而需要修改配置文件，如下所示：

[root@docker1 ~]# vim? /etc/systemd/system/docker.service.d/10-machine.conf （加粗內(nèi)容是需要添加的）

[Service]

ExecStart=

ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:2376 -H unix:///var/run/docker.sock --storage-driver devicemapper --tlsverify --tlscacert /etc/docker/ca.pem --tlscert /etc/docker/server.pem --tlskey /etc/docker/server-key.pem --label provider=generic --cluster-store=consul://192.168.0.10:8500 --cluster-advertise=ens32:2376

Environment=

參數(shù)說(shuō)明：

--cluster-store主要表示為需要連接的kv存儲(chǔ)的地址，--cluster-advertise表示使用哪個(gè)網(wǎng)卡和端口來(lái)進(jìn)行通信。ens32表示為網(wǎng)卡的名稱或者使用主機(jī)的ip地址。

[root@docker1 ~]# systemctl daemon-reload（重新加載配置文件）

[root@docker1 ~]# systemctl restart docker（重新啟動(dòng)服務(wù)）

docker2上同樣進(jìn)行上述操作

再次查看kv存儲(chǔ)，發(fā)現(xiàn)已經(jīng)注冊(cè)，注意在點(diǎn)擊的時(shí)候，需要先點(diǎn)擊key/value,然后再點(diǎn)擊docker，最后點(diǎn)擊nodes才能看到注冊(cè)的主機(jī)

3. 創(chuàng)建overlay網(wǎng)絡(luò)

[root@docker1 ~]# docker network ls

NETWORK ID? ? ? ? ? NAME? ? ? ? ? ? ? ? DRIVER? ? ? ? ? ? ? SCOPE

ef17c0c56159? ? ? ? bridge? ? ? ? ? ? ? bridge? ? ? ? ? ? ? local

34963f83928c? ? ? ? host? ? ? ? ? ? ? ? host? ? ? ? ? ? ? ? local

a79f72191b90? ? ? ? none? ? ? ? ? ? ? ? null? ? ? ? ? ? ? ? local

[root@docker1 ~]#? docker network create -d overlay kel? ? //（創(chuàng)建overlay網(wǎng)絡(luò)）

8675d048411335e1738996b62fb9e505e270379a3efd1a4af2a9f7b96c03dd1f

[root@docker1 ~]# docker network ls

NETWORK ID? ? ? ? ? NAME? ? ? ? ? ? ? ? DRIVER? ? ? ? ? ? ? SCOPE

ef17c0c56159? ? ? ? bridge? ? ? ? ? ? ? bridge? ? ? ? ? ? ? local

34963f83928c? ? ? ? host? ? ? ? ? ? ? ? host? ? ? ? ? ? ? ? local

8675d0484113? ? ? ? kel? ? ? ? ? ? ? ? overlay? ? ? ? ? ? global

a79f72191b90? ? ? ? none? ? ? ? ? ? ? ? null? ? ? ? ? ? ? ? local

[root@docker2 ~]# docker network ls? ? ? ?//（在主機(jī)docker1上也能看到此網(wǎng)絡(luò)）

NETWORK ID? ? ? ? ? NAME? ? ? ? ? ? ? ? DRIVER? ? ? ? ? ? ? SCOPE

d78fa5f31c2a? ? ? ? bridge? ? ? ? ? ? ? bridge? ? ? ? ? ? ? local

34963f83928c? ? ? ? host? ? ? ? ? ? ? ? host? ? ? ? ? ? ? ? local

8675d0484113? ? ? ? kel? ? ? ? ? ? ? ? overlay? ? ? ? ? ? global

a79f72191b90? ? ? ? none? ? ? ? ? ? ? ? null? ? ? ? ? ? ? ? local

4. 創(chuàng)建容器測(cè)試網(wǎng)絡(luò)連通性

[root@docker1 ~]# docker pull cirros

Using default tag: latest

latest: Pulling from library/cirros

480d57c7bf4d: Pull complete

0f45bfe9a805: Pull complete

5aa6c26e64dc: Pull complete

Digest: sha256:e67f6f4a0521e326ba2dd697950046aba5ce836edda79cb818d45a56841c7ca2

Status: Downloaded newer image for cirros:latest

[root@docker1 ~]# docker run -itd --name b1 --network=kel cirros? //（運(yùn)行一個(gè)網(wǎng)絡(luò)在kel網(wǎng)絡(luò)中的容器）

/ # ifconfig

eth0? ? ? Link encap:Ethernet? HWaddr 02:42:0A:00:00:04?

? ? ? ? ? inet addr:10.0.0.2? Bcast:10.0.0.255? Mask:255.255.255.0

? ? ? ? ? UP BROADCAST RUNNING MULTICAST? MTU:1450? Metric:1

? ? ? ? ? RX packets:0 errors:0 dropped:0 overruns:0 frame:0

? ? ? ? ? TX packets:0 errors:0 dropped:0 overruns:0 carrier:0

? ? ? ? ? collisions:0 txqueuelen:0

? ? ? ? ? RX bytes:0 (0.0 B)? TX bytes:0 (0.0 B)

[root@docker2 ~]# docker run -itd --name b2 --network=kel cirros? ? //（在另一臺(tái)主機(jī)上運(yùn)行一個(gè)kel網(wǎng)段中的容器）

/ # ifconfig

eth0? ? ? Link encap:Ethernet? HWaddr 02:42:0A:00:00:03?

? ? ? ? ? inet addr:10.0.0.3? Bcast:10.0.0.255? Mask:255.255.255.0

? ? ? ? ? UP BROADCAST RUNNING MULTICAST? MTU:1450? Metric:1

? ? ? ? ? RX packets:0 errors:0 dropped:0 overruns:0 frame:0

? ? ? ? ? TX packets:0 errors:0 dropped:0 overruns:0 carrier:0

? ? ? ? ? collisions:0 txqueuelen:0

? ? ? ? ? RX bytes:0 (0.0 B)? TX bytes:0 (0.0 B)

/# ip r? ?//(查看路由）

default via 172.18.0.1 dev eth1

10.0.0.0/24 dev eth0 scope link? src 10.0.0.2

172.18.0.0/16 dev eth1 scope link? src 172.18.0.2

/ # cat /etc/resolv.conf? ? //(自帶的DNS解析）

nameserver 127.0.0.11

options ndots:0

/ # ip addr show? ? //（有兩個(gè)網(wǎng)絡(luò)接口）

1: lo: mtu 65536 qdisc noqueue qlen 1

? ? 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

7: eth0@if8: mtu 1450 qdisc noqueue

? ? link/ether 02:42:0a:00:00:02 brd ff:ff:ff:ff:ff:ff

? ? inet 10.0.0.2/24 brd 10.0.0.255 scope global eth0

? ? ? valid_lft forever preferred_lft forever

10: eth1@if11: mtu 1500 qdisc noqueue

? ? link/ether 02:42:ac:12:00:02 brd ff:ff:ff:ff:ff:ff

? ? inet 172.18.0.2/16 brd 172.18.255.255 scope global eth1

? ? ? valid_lft forever preferred_lft forever

5. 不同宿主機(jī)內(nèi)容器互通測(cè)試

docker1內(nèi)容器

/ # ping b2 （跨主機(jī)ping)

PING b2 (10.0.0.3): 56 data bytes

64 bytes from 10.0.0.3: seq=0 ttl=64 time=19.570 ms

64 bytes from 10.0.0.3: seq=1 ttl=64 time=3.206 ms

--- b2 ping statistics ---

2 packets transmitted, 2 packets received, 0% packet loss

round-trip min/avg/max = 3.206/11.388/19.570 ms

docker2內(nèi)容器

/# ping b1

PING 10.0.0.2 (10.0.0.2): 56 data bytes

64 bytes from 10.0.0.2: seq=0 ttl=64 time=37.227 ms

64 bytes from 10.0.0.2: seq=1 ttl=64 time=0.448 ms

--- 10.0.0.2 ping statistics ---

2 packets transmitted, 2 packets received, 0% packet loss

round-trip min/avg/max = 0.448/18.837/37.227 ms

原創(chuàng)作品，允許轉(zhuǎn)載，轉(zhuǎn)載時(shí)請(qǐng)務(wù)必以超鏈接形式標(biāo)明文章 原始出處 、作者信息和本聲明。