rh358 003 ansible部署双网卡绑定 DNS原理 bind正向解析
双网卡绑定
绑定多张网卡成为逻辑口，从而实现链路冗余，以及数据流量的负载均衡
1.创建team口
[root@servera ~]# nmcli connection add type team con-name team0 ifname team0 team.runner activebackup ipv4.method manual ipv4.address 192.168.0.200/24
Connection 'team0' (3eb2f94e-3653-4aa2-a3f1-0826a02b26d1) successfully added.
创建了链接
[root@servera ~]# nmcli connection show
NAME UUID TYPE DEVICE
team0 e4a115a2-5444-4d16-975b-5d1fc62a2503 team team0
创建了链接配置文件
[root@servera ~]# cat /etc/sysconfig/network-scripts/ifcfg-team0
TEAM_CONFIG="{ \"runner\": { \"name\": \"activebackup\" } }"
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=dhcp
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=team0
UUID=e4a115a2-5444-4d16-975b-5d1fc62a2503
DEVICE=team0
ONBOOT=yes
DEVICETYPE=Team
[root@servera ~]#
创建了team0设备
[root@servera ~]# nmcli device
DEVICE TYPE STATE CONNECTION
eth0 ethernet connected Wired connection 1
eth1 ethernet connected eth1
team0 team [connecting (getting IP configuration)] team0
team逻辑口一直无法获取dhcp，那么他会自动消失
如果是manual则无视此问题
也可以使用modify修改 team0
2.把物理网卡加入team中
建议删除网卡关联的旧链接
[root@servera ~]# nmcli connection delete 'Wired connection 2'
Connection 'Wired connection 2' (8f9a19e2-d15a-3772-b71d-320159e6753d) successfully deleted.
[root@servera ~]# nmcli connection delete 'eth1'
Connection 'eth1' (1e60e42a-10e8-4a27-ba92-c5698ae322c1) successfully deleted.
[root@servera ~]#
添加新链接，绑定逻辑接口
[root@servera ~]# nmcli connection add type ethernet slave-type team con-name eth1 ifname eth1 master team0
Connection 'eth1' (17ef3f96-7b48-42a4-a0bd-11341eaec928) successfully added.
[root@servera ~]# nmcli connection add type ethernet slave-type team con-name eth2 ifname eth2 master team0
Connection 'eth2' (18fc1852-1b11-4f98-89a1-fb898f5e6bb2) successfully added.
[root@servera ~]#
[root@servera ~]# nmcli connection show
NAME UUID TYPE DEVICE
mqy bffa0efd-a0c4-40c6-ad27-ff42ccd5dc1c ethernet eth1
team0 e4a115a2-5444-4d16-975b-5d1fc62a2503 team team0
Wired connection 1 4ae4bb9e-8f2d-3774-95f8-868d74edcc3c ethernet eth0
eth2 18fc1852-1b11-4f98-89a1-fb898f5e6bb2 ethernet eth2
eth1 17ef3f96-7b48-42a4-a0bd-11341eaec928 ethernet --
[root@servera ~]# nmcli device
DEVICE TYPE STATE CONNECTION
eth0 ethernet connected Wired connection 1
team0 team connected team0
eth1 ethernet connected eth1
eth2 ethernet connected eth2
如果team0无ip地址，则使用nmcli connection down 然后 up
7: team0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 52:54:00:02:fa:0a brd ff:ff:ff:ff:ff:ff
inet 192.168.0.200/24 brd 192.168.0.255 scope global noprefixroute team0
valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel [master team0 state UP] group default qlen 1000
link/ether 52:54:00:02:fa:0a brd ff:ff:ff:ff:ff:ff
4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel [master team0 state UP] group default qlen 1000
需要注意几个点
物理网卡不需要配置ip地址，所有的ip地址都在team口配置
只有当物理接口存在up的情况下team口才会up
3.查看team配置网络信息
查看team信息
[root@servera ~]# teamdctl team0 state
setup:
runner: activebackup
ports:
eth1
link watches:
link summary: up
instance[link_watch_0]:
name: ethtool 使用ethtool来监控
link: up
down count: 0
eth2
link watches:
link summary: up
instance[link_watch_0]:
name: ethtool
link: up
down count: 0
runner:
active port: eth1
查看配置信息
[root@servera ~]# teamdctl team0 config dump
{
"device": "team0",
"mcast_rejoin": {
"count": 1
},
"notify_peers": {
"count": 1
},
"ports": {
"eth1": {
"link_watch": {
"name": "ethtool"
}
},
"eth2": {
"link_watch": {
"name": "ethtool"
}
}
},
"runner": {
"name": "activebackup"
}
}
[root@servera ~]#
team0 config dump noport#不要接口信息
直接查看接口状态
[root@servera ~]# teamnl team0 ports
4: eth2: up 4294967295Mbit FD
3: eth1: up 4294967295Mbit FD
team口的网卡配置文件
[root@servera ~]# cat /etc/sysconfig/network-scripts/ifcfg-team0
TEAM_CONFIG="{ \"runner\": { \"name\": \"activebackup\" } }"
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=none
IPADDR=192.168.0.200
PREFIX=24
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=team0
UUID=3eb2f94e-3653-4aa2-a3f1-0826a02b26d1
DEVICE=team0
ONBOOT=yes
DEVICETYPE=Team
[root@servera ~]#
[root@servera ~]# teamdctl team0 config dump > t1.json
[root@servera ~]# vi t1.json
"runner": {
"name": "roundrobin"
}
}
[root@servera ~]# nmcli connection modify team0 team.config t1.json
[root@servera ~]# cat /etc/sysconfig/network-scripts/ifcfg-team0
TEAM_CONFIG=$'{\n \"device\": \"team0\",\n \"mcast_rejoin\": {\n \"count\": 1\n },\n \"notify_peers\": {\n \"count\": 1\n },\n \"ports\": {\n \"eth1\": {\n \"link_watch\": {\n \"name\": \"ethtool\"\n }\n },\n \"eth2\": {\n \"link_watch\": {\n \"name\": \"ethtool\"\n }\n }\n },\n \"runner\": {\n \"name\": \"roundrobin\"\n }\n}\n'
PROXY_METHOD=none
第二种改法
[root@servera ~]# nmcli connection modify team0 team.runner activebackup
[root@servera ~]# nmcli connection up team0
Connection successfully activated (master waiting for slaves) (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/27)
[root@servera ~]#
[root@servera ~]# teamdctl team0 config dump
{
"device": "team0",
"mcast_rejoin": {
"count": 1
},
"notify_peers": {
"count": 1
},
"ports": {
"eth1": {
"link_watch": {
"name": "ethtool"
}
},
"eth2": {
"link_watch": {
"name": "ethtool"
}
}
},
"runner": {
"name": "activebackup"
}
}
无论如何都得 nmcli connection up team0 来打开team0，去读取配置文件
利用ansible
使用系统role提供正确的变量，就可以完成任务
[student@workstation ~]$ lab netlink-automation start
Starting netlink-automation exercise.
· Create Ansible project directory............................ SUCCESS
· Download Ansible configuration.............................. SUCCESS
· Download Ansible inventory.................................. SUCCESS
· Configuring eth1 network interface on serverd............... SUCCESS
[student@workstation ~]$
肯定需要这个角色包
[student@workstation ~]$ sudo yum -y install rhel-system-roles
准备剧本
[student@workstation ~]$ ll
total 0
drwxr-xr-x. 2 student student 42 Sep 3 22:10 netlink-automation
drwxr-xr-x. 2 student student 42 Aug 29 08:02 servicemgmt-automation
[student@workstation ~]$ cd netlink-automation/
[student@workstation netlink-automation]$ ls
ansible.cfg inventory
[student@workstation netlink-automation]$ ansible-galaxy list
# /usr/share/ansible/roles
- linux-system-roles.kdump, (unknown version)
- linux-system-roles.network, (unknown version)
- linux-system-roles.postfix, (unknown version)
- linux-system-roles.selinux, (unknown version)
- linux-system-roles.storage, (unknown version)
- linux-system-roles.timesync, (unknown version)
[root@servera ~]# nmcli device
DEVICE TYPE STATE CONNECTION
eth0 ethernet connected Wired connection 1
team0 team connected team0
eth1 ethernet connected eth1
eth2 ethernet connected eth2
[root@servera ~]# teamdctl team0 config dump
{
"device": "team0",
"ports": {
"eth1": {
"link_watch": {
"name": "ethtool"
}
},
"eth2": {
"link_watch": {
"name": "ethtool"
}
}
},
"runner": {
"name": "roundrobin"
}
}
[root@servera ~]#
此角色无更改runner的功能，继续更改playbook
[root@servera ~]# teamdctl team0 config dump
{
"device": "team0",
"mcast_rejoin": {
"count": 1
},
"notify_peers": {
"count": 1
},
"ports": {
"eth1": {
"link_watch": {
"name": "ethtool"
}
},
"eth2": {
"link_watch": {
"name": "ethtool"
}
}
},
"runner": {
"name": "activebackup"
}
}
[root@servera ~]#
成功
但是这无法体现幂等性，最后三条command总会重复执行，没有意义。增加判断条件
第一个is not defined 首先判断这个接口是否存在，不存在执行roles
第二个not in 判断这个是否有activebackup 有则改，无则跳过
反复执行不会有多余的操作
bond比team更适应交换机
管理DNS
DNS的层级结构
树状结构
.代表根域-->每个域都有对应的DNS服务器:域名->IP
根域服务器: 13台 （iPv4）
根域下面就是二级子域 .com .cn .net .edu .gov 域名
举个例子
lab.example.com(三级)是example.com(二级)的子域
example.com是.com(一级)的子域
fqdn:完全合格名称 --> ip (能被dns解析)
主机名得与fqdn区分
DNS服务器到底保存了什么内容
1： DNS服务器：到底保存了什么内容，DNS的工作原理
lab.example.com<域名> DNSserver Servera
1> 授权的子域，以及子域的DNS服务
ocp4.lab.example.com<域名>是lab.example.com的子域
master01.ocp4.lab.example.com <serverb.lab.example >
你必须在lab.example.com 的DNS服务器配置ocp4.lab.example.com 的DNS服务器在serverb.lab.example.com.
也就是上级域，必须要有下级域名的DNS服务器
2> 该域下所有的FQDN的解析也成为区域配置文件
servera.lab.example.com 172.25.250.10
serverb.lab.example.com 172.25.250.11
3> 根域服务器的IP地址
DNS解析过程分为： 一个是递归
这是在没有DNS缓存服务器的情况下，去找根域。很麻烦
有缓存服务器的情况下就不需要找根域，更有效率
实验：通过bind实现正向，反向，转发，主从，各种资源记录 (未完结)
1> 安装软件包: serverb
[root@serverb ~]# yum install -y bind
2> 修改配置文件
[root@serverb ~]# vim /etc/named.conf 配置文件路径
//代表注释
options {
// listen-on port 53 { 127.0.0.1; };监听的端口是53：
DNS既监听UDP53还有TCP53，TCP53端口用于主从同步用的UDP53用于查询的
listen-on port 53 { 172.25.250.11;127.0.0.1; };
directory "/var/named"; 类似于定于了一个/目录，数据文件都放哪里
dump-file "/var/named/data/cache_dump.db";备份文件
statistics-file "/var/named/data/named_stats.txt"; 统计
memstatistics-file "/var/named/data/named_mem_stats.txt";
secroots-file "/var/named/data/named.secroots";
recursing-file "/var/named/data/named.recursing";
// allow-query { localhost; }; 允许谁来查寻
allow-query { 172.25.250.0/24; };
recursion yes; 是否允许递归查询。如果你的DNS服务仅仅是解析自己域内FQDN，则不需要递归，如果需要解析其他域内的FQDN则需要配置递归，设置为YES
dnssec-enable no;
dnssec-validation no; 有关安全的 秘钥之类
logging {
channel default_debug {
file "data/named.run";->/var/named/data/named.run
severity dynamic; #日志路径
};
};
3> 配置区域配置文件zone...区域配置文件，指定的是该域内所有资源解析的文件FQND-->ip （重点，fqdn的对应关系）
分为正向解析区域配置文件，反向解析区域配置文件
正向区域配置文件：
zone "." IN {
type hint;
file "named.ca";
};
根域地址
zone "example.com" IN {
type master ;
file "example.com"; 该域：example.com的区域配置文件在/var/named/example.com
};
4> 准备这个区域配置文件
[root@serverb ~]# cp /var/named/named.empty /var/named/example.com
[root@serverb ~]# chown root:named /var/named/example.com 属组一定要是这个named这个组
[root@serverb ~]# chmod 640 /var/named/example.com
[root@serverb ~]# ll -lZ /var/named/example.com
-rw-r-----. 1 root named unconfined_u:object_r:named_zone_t:s0 152 Sep 3 19:40 /var/named/example.com
[root@serverb ~]# vim /var/named/example.com
$TTL 3H # 缓存时间 # @代表本域（example.com） # SOA 记录表示此域名的权威解析服务器地址 从域名到ip记录称之为A记录 soa后面是管理者邮箱 root后面不能是@
@ IN SOA serverb.example.com. root.serverb.example.com. (
0 ; serial [改了配置文件这个数字+1 就可以同步]
1D ; refresh
1H ; retry
1W ; expire
3H ) ; minimum
@ IN NS serverb.example.com.
servera IN A 172.25.250.10
serverb IN A 172.25.250.11
serverc IN A 172.25.250.12
serverd IN A 172.25.250.13
kevin IN CNAME serverc
5>启动服务，开放防火墙
[root@serverb ~]# systemctl enable --now named.service
[root@serverb ~]#
[root@serverb ~]# firewall-cmd --permanent --add-port=53/tcp
success
[root@serverb ~]# firewall-cmd --permanent --add-port=53/udp
success
[root@serverb ~]# firewall-cmd --reload
6> 登录servera
[root@servera ~]# cat /etc/resolv.conf
# Generated by NetworkManager
search lab.example.com example.com
nameserver 172.25.250.11
[root@servera ~]# ping kevin
PING serverc.example.com (172.25.250.12) 56(84) bytes of data.
64 bytes from serverc.lab.example.com (172.25.250.12): icmp_seq=1 ttl=64 time=0.728 ms
64 bytes from serverc.lab.example.com (172.25.250.12): icmp_seq=2 ttl=64 time=0.733 ms
^C
[root@servera ~]# ping servera.example.com
PING servera.example.com (172.25.250.10) 56(84) bytes of data.
64 bytes from servera.lab.example.com (172.25.250.10): icmp_seq=1 ttl=64 time=0.026 ms
64 bytes from servera.lab.example.com (172.25.250.10): icmp_seq=2 ttl=64 time=0.046 ms
^C
--- servera.example.com ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 26ms
rtt min/avg/max/mdev = 0.026/0.036/0.046/0.010 ms
[root@servera ~]# ping serverb.example.com
PING serverb.example.com (172.25.250.11) 56(84) bytes of data.
64 bytes from serverb.lab.example.com (172.25.250.11): icmp_seq=1 ttl=64 time=0.744 ms
64 bytes from serverb.lab.example.com (172.25.250.11): icmp_seq=2 ttl=64 time=0.693 ms
^C
--- serverb.example.com ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 51ms
rtt min/avg/max/mdev = 0.693/0.718/0.744/0.037 ms
[root@servera ~]# ping serverc.example.com
PING serverc.example.com (172.25.250.12) 56(84) bytes of data.
64 bytes from serverc.lab.example.com (172.25.250.12): icmp_seq=1 ttl=64 time=1.66 ms
64 bytes from serverc.lab.example.com (172.25.250.12): icmp_seq=2 ttl=64 time=2.88 ms
^C
