某校园网要架设一台主DNS服务器负责linux-xxx域(xxx为姓名拼音或首字母)的域名解析工作，服务器IP地址为192.168.1.学号。 要求：1、为以下域名实现正向和反向域名解析服务。 dns.linux-xxx.com 192.168.1.学号 mail.linux-xxx.com MX记录 192.168.1.180 study.linux-xxx.com 192.168.1.181 teach.linux-xxx.com 192.168.1.182 www.linux-xxx.com 192.168.1.183 2、配置从DNS服务器，IP地址为192.168.1.199 3、其它虚拟机设置以上主从DNS服务器测试正常。 4、windows主机设置以上主从DNS服务器测试正常。在Centos7完成这些要求，并给出具体步骤。

以下是在CentOS 7上完成这些要求的具体步骤：

1. 安装BIND软件包：

yum install bind bind-utils -y

2. 编辑主DNS服务器的配置文件`/etc/named.conf`，添加以下内容：

acl "trusted" {
    192.168.1.0/24;
    localhost;
};

options {
    directory "/var/named";
    recursion yes;
    allow-query { trusted; };
    forwarders { 8.8.8.8; };
};

zone "linux-xxx.com" IN {
    type master;
    file "linux-xxx.com.zone";
    allow-update { none; };
};

zone "1.168.192.in-addr.arpa" IN {
    type master;
    file "1.168.192.in-addr.arpa.zone";
    allow-update { none; };
};

3. 创建正向解析区域文件`/var/named/linux-xxx.com.zone`，添加以下内容：

$TTL 86400
@ IN SOA dns.linux-xxx.com. root.linux-xxx.com. (
    2021100101; Serial
    3600; Refresh after 3 hours
    900; Retry after 15 minutes
    604800; Expire after 1 week
    86400); Minimum TTL of 1 day

@ IN NS dns.linux-xxx.com.

dns.linux-xxx.com. IN A 192.168.1.学号
mail.linux-xxx.com. IN MX 10 192.168.1.180
study.linux-xxx.com. IN A 192.168.1.181
teach.linux-xxx.com. IN A 192.168.1.182
www.linux-xxx.com. IN A 192.168.1.183

4. 创建反向解析区域文件`/var/named/1.168.192.in-addr.arpa.zone`，添加以下内容：

$TTL 86400
@ IN SOA dns.linux-xxx.com. root.linux-xxx.com. (
    2021100101; Serial
    3600; Refresh after 3 hours
    900; Retry after 15 minutes
    604800; Expire after 1 week
    86400); Minimum TTL of 1 day

@ IN NS dns.linux-xxx.com.

学号 IN PTR dns.linux-xxx.com.
180 IN PTR mail.linux-xxx.com.
181 IN PTR study.linux-xxx.com.
182 IN PTR teach.linux-xxx.com.
183 IN PTR www.linux-xxx.com.

5. 启动并开机自启BIND服务：

systemctl start named
systemctl enable named

6. 编辑从DNS服务器的配置文件`/etc/named.conf`，添加以下内容：

options {
    directory "/var/named";
    recursion yes;
    allow-query { any; };
};

zone "linux-xxx.com" IN {
    type slave;
    masters { 192.168.1.学号; };
    file "slaves/linux-xxx.com.zone";
};

zone "1.168.192.in-addr.arpa" IN {
    type slave;
    masters { 192.168.1.学号; };
    file "slaves/1.168.192.in-addr.arpa.zone";
};

7. 启动并开机自启BIND服务：

systemctl start named
systemctl enable named

8. 在其它虚拟机和Windows主机上配置主从DNS服务器的IP地址，测试解析是否正常。

注意：在上述步骤中，需要将其中的`linux-xxx.com`和`学号`替换为具体的域名和IP地址。在创建区域文件时，需要注意修改文件名和目录路径，以避免与已有文件重名。