Extended-range VLANs：
VTP only learns about normal-range VLANs (VLAN IDs 1 to 1005). Extended-range VLANs (VLAN IDs greater than 1005) are not supported by VTP or stored in the VTP VLAN database.
Configuring Extended-Range VLANs
When the switch is in VTP transparent mode (VTP disabled), you can create extended-range VLANs (in the range 1006 to 4094). Extended-range VLANs enable service providers to extend their infrastructure to a greater number of customers. The extended-range VLAN IDs are allowed for any switchport commands that allow VLAN IDs. You always use config-vlan mode (accessed by entering the vlan vlan-id global configuration command) to configure extended-range VLANs. The extended range is not supported in VLAN database configuration mode (accessed by entering the vlan database privileged EXEC command). Extended-range VLAN configurations are not stored in the VLAN database, but because VTP mode is transparent, they are stored in the switch running configuration file, and you can save the configuration in the startup configuration file by using the copy running-config startup-config privileged EXEC command.
Extended-Range VLAN Configuration Guidelines
Follow these guidelines when creating extended-range VLANs:
• To add an extended-range VLAN, you must use the vlan vlan-id global configuration command and access config-vlan mode. You cannot add extended-range VLANs in VLAN database configuration mode (accessed by entering the vlan database privileged EXEC command).
• VLAN IDs in the extended range are not saved in the VLAN database and are not recognized by VTP.
• You cannot include extended-range VLANs in the pruning eligible range.
• The switch must be in VTP transparent mode when you create extended-range VLANs. If VTP mode is server or client, an error message is generated, and the extended-range VLAN is rejected.
• You can set the VTP mode to transparent in global configuration mode or in VLAN database configuration mode. You should save this configuration to the startup configuration so that the switch boots up in VTP transparent mode. Otherwise, you lose the extended-range VLAN configuration if the switch resets.
• STP is enabled by default on extended-range VLANs, but you can disable it by using the no spanning-tree vlan vlan-id global configuration command. When the maximum number of spanning-tree instances are on the switch, spanning tree is disabled on any newly created VLANs. If the number of VLANs on the switch exceeds the maximum number of spanning-tree instances, we recommend that you configure the IEEE 802.1s Multiple STP (MSTP) on your switch to map multiple VLANs to a single spanning-tree instance.
• Although the switch supports a total of 1005 (normal-range and extended-range) VLANs, the number of routed ports, SVIs, and other configured features affects the use of the switch hardware. If you try to create an extended-range VLAN and there are not enough hardware resources available, an error message is generated, and the extended-range VLAN is rejected.
Creating an Extended-Range VLAN
Extended-range VLANs are not saved in the VLAN database; they are saved in the switch running configuration file. You can save the extended-range VLAN configuration in the switch startup configuration file by using the copy running-config startup-config privileged EXEC command.
This example shows how to create a new extended-range VLAN with all default characteristics, enter config-vlan mode, and save the new VLAN in the switch startup configuration file:
Switch(config)# vtp mode transparent
Switch(config)# vlan 2000
Switch(config-vlan)# end
Switch# copy running-config startup config
源引：http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_44_se/configuration/guide/swvlan.html#wp1200242
VTP in Cisco Configuration Guide:http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_44_se/configuration/guide/swvtp.html
2009/02/27
修复重装XP后的Ubuntu引导分区
当我们重装了windows以后，由于硬盘mbr被重写，即把原来mbr中grub的信息清除了，那么grub自然就不能启动了，也就不能引导linux了，此时很多人可能就只能重装linux了，但其实只需简单的对mbr修复一下就可以了。
下面就说一下修复mbr的方法：
首先，把Ubuntu的安装光盘放进去,然后启动.正常进入安装界面，打开终端：
1、输入：sudo grub,于是变成grub>
2、先找到你的ubuntu的启动分区在哪(就是你的/boot目录所在的分区)输入：find /boot/grub/stage1 or find /grub/stage1我机器上回车之后显示：(hd0,7)这里hd0是指第一个硬盘,7代表第8个分区，即Ubuntu根目录所在分区(0代表第一个分区)。
3、输入：grub>root(hd0,7)
4、输入：grub>setup(hd0)如果出现successed，就表示成功了。
5、输入：grub>quit，然后重启。
对于有多个硬盘的朋友，请但是注意一点，如果你的windows装在第一块磁盘，而linux装在第二块磁盘，而你的bios设置为从第一块磁盘启动，那么在进行以上第3步的时候，一定要把参数设为你的第一块磁盘，即要把grub装入引导硬盘的mbr里。
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以上修复引导分区的方法已经得到验证。
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