2006年10月27日 20:38
A类网络划分子网数与对应的子网掩码
子网数目 占用主机号位数 子网掩码 子网中可容纳的主机数
2 1 255.128.0.0 8388606
4 2 255.192.0.0 4194302
8 3 255.224.0.0 2097150
16 4 255.240.0.0 1048574
32 5 255.258.0.0 524286
64 6 255.253.0.0 262142
128 7 255.254.0.0 131070
256 8 255.255.0.0 65534
子网数目 占用主机号位数 子网掩码 子网中可容纳的主机数
2 1 255.128.0.0 8388606
4 2 255.192.0.0 4194302
8 3 255.224.0.0 2097150
16 4 255.240.0.0 1048574
32 5 255.258.0.0 524286
64 6 255.253.0.0 262142
128 7 255.254.0.0 131070
256 8 255.255.0.0 65534
2006年10月25日 20:51
对于Windows下ping命令相信大家已经再熟悉不过了，但是能把ping的功能发挥到最大的人却并不是很多，当然我也并不是说我可以让ping发挥最大的功能，我也只不过经常用ping这个工具，也总结了一些小经验，现在和大家分享一下。
现在我就参照ping命令的帮助说明来给大家说说我使用ping时会用到的技巧，ping只有在安装了TCP/IP协议以后才可以使用：
ping [-t] [-a] [-n count] [-l length] [-f] [-i ttl] [-v tos] [-r count] [-s count] [[-j computer-list] | [-k computer-list]] [-wz timeout] destination-list
Options:
-t Ping the specified host until stopped.To see statistics and continue - type Control-Break;To stop - type Control-C.
不停的ping地方主机，直到你按下Control-C。
此功能没有什么特别的技巧，不过可以配合其他参数使用，将在下面提到。
现在我就参照ping命令的帮助说明来给大家说说我使用ping时会用到的技巧，ping只有在安装了TCP/IP协议以后才可以使用：
ping [-t] [-a] [-n count] [-l length] [-f] [-i ttl] [-v tos] [-r count] [-s count] [[-j computer-list] | [-k computer-list]] [-wz timeout] destination-list
Options:
-t Ping the specified host until stopped.To see statistics and continue - type Control-Break;To stop - type Control-C.
不停的ping地方主机，直到你按下Control-C。
此功能没有什么特别的技巧，不过可以配合其他参数使用，将在下面提到。
2006年10月23日 22:44
#1251 - Client does not support authentication protocol requested by server; consider upgrading MySQL client
MySQL 4.1 and up uses an authentication protocol based on a password hashing algorithm that is incompatible with that used by older clients. If you upgrade the server to 4.1, attempts to connect to it with an older client may fail with the following message:
shell> mysql
Client does not support authentication protocol requested
by server; consider upgrading MySQL client
To solve this problem, you should use one of the following approaches:
Upgrade all client programs to use a 4.1.1 or newer client library.
When connecting to the server with a pre-4.1 client program, use an account that still has a pre-4.1-style password.
Reset the password to pre-4.1 style for each user that needs to use a pre-4.1 client program. This can be done using the SET PASSWORD statement and the OLD_PASSWORD() function:
mysql> SET PASSWORD FOR
-> 'some_user'@'some_host' = OLD_PASSWORD('newpwd');
alternatively, use update and FLUSH PRIVILEGES:
mysql> update mysql.user SET Password = OLD_PASSWORD('newpwd')
-> where Host = 'some_host' AND User = 'some_user';
mysql> FLUSH PRIVILEGES;
Substitute the password you want to use for ``newpwd'' in the preceding examples. MySQL cannot tell you what the original password was, so you'll need to pick a new one.
Tell the server to use the older password hashing algorithm:
Start mysqld with the --old-passwords option.
Assign an old-format password to each account that has had its password updated to the longer 4.1 format. You can identify these accounts with the following query:
mysql> select Host, User, Password FROM mysql.user
-> where LENGTH(Password) > 16;
For each account record displayed by the query, use the Host and User values and assign a password using the OLD_PASSWORD() function and either SET PASSWORD or update, as described earlier.
For additional background on password hashing and authentication, see Section 5.5.9, "Password Hashing in MySQL 4.1".
Previous / Next / Up / Table of Contents
MySQL 4.1 and up uses an authentication protocol based on a password hashing algorithm that is incompatible with that used by older clients. If you upgrade the server to 4.1, attempts to connect to it with an older client may fail with the following message:
shell> mysql
Client does not support authentication protocol requested
by server; consider upgrading MySQL client
To solve this problem, you should use one of the following approaches:
Upgrade all client programs to use a 4.1.1 or newer client library.
When connecting to the server with a pre-4.1 client program, use an account that still has a pre-4.1-style password.
Reset the password to pre-4.1 style for each user that needs to use a pre-4.1 client program. This can be done using the SET PASSWORD statement and the OLD_PASSWORD() function:
mysql> SET PASSWORD FOR
-> 'some_user'@'some_host' = OLD_PASSWORD('newpwd');
alternatively, use update and FLUSH PRIVILEGES:
mysql> update mysql.user SET Password = OLD_PASSWORD('newpwd')
-> where Host = 'some_host' AND User = 'some_user';
mysql> FLUSH PRIVILEGES;
Substitute the password you want to use for ``newpwd'' in the preceding examples. MySQL cannot tell you what the original password was, so you'll need to pick a new one.
Tell the server to use the older password hashing algorithm:
Start mysqld with the --old-passwords option.
Assign an old-format password to each account that has had its password updated to the longer 4.1 format. You can identify these accounts with the following query:
mysql> select Host, User, Password FROM mysql.user
-> where LENGTH(Password) > 16;
For each account record displayed by the query, use the Host and User values and assign a password using the OLD_PASSWORD() function and either SET PASSWORD or update, as described earlier.
For additional background on password hashing and authentication, see Section 5.5.9, "Password Hashing in MySQL 4.1".
Previous / Next / Up / Table of Contents
2006年10月22日 20:52
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生产加工类
生产加工电子元器件、家具、玩具、工艺品、竹木制品等等。（公司名称参考：上海XX家具制造/服装加工有限公司等等）
2006年10月21日 20:24
Windows 会将我们访问过的 DNS 条目缓存下来供下次解析该域名时使用, 我们可以通过在注册表添加一下项目老控制 Cache 的有效期 HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings Value Name: DnsCacheTimeout Data Type: REG_DWORD Radix: Decimal Value: (time in seconds) Value Name: ServerInfoTimeOut Data Type: REG_DWORD Radix: Decimal Value: (time in seconds) 但是有时候我们不能随意改变用户机器中的相关设定，而且我们也只是需要在特定情况下立即刷新本地 DNS 缓存，查阅 MSDN 后没有找到相关方法。Windows 的组件 ipconfig.exe 提供了一个刷新 DNS 的命令行参数，"ipconfig /flushdns".
