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5505 stuck in VTP transparent

I have a 5505 that refuses to change VTP mode to anything other than transparent. It acts as though it has taken the change, but when you show vtp domain, it shows it as back in transparent mode. The VTP server is a 2924, and there is another 5505 in the network as a client(Which occasionaly slips back to transparent, but takes the change back to client). The only difference between the two 5505s is a slightly older COS on the one that is stuck in transparent ( 6.3(5) vs. 6.4(17) ). Due to the fact that the switch is in heavy usage and they take a while to bring back up, I can't randomly play with it unless I'm fairly sure I've found a solution. There are around 150 VLANs in the database. The server is running VTP V1(as is the 5505 in question). The 5505 does not show any other signs of failure, it's been rock solid otherwise. It's just getting to be a pain having to enter VLAN changes in on 2 switches instead of one. The domain name is the same. I can't find anything in the Cisco release notes that ever shows this as a known problem.


Re: 5505 stuck in VTP transparent

The vtp server should not be the 2924 which may be your problem . These will only support like 64 spanning tree instances so anything above that means spanning tree is not working for those vlans . The 2924 should be a client and you should manually prune the connecting links of vlans that are not needed on the 2924 . Always use the more powerful box as the server . Make the 5500 the server . Below is some info from a cisco webpage.

upported STP Instances

You create an STP instance when you assign an interface to a VLAN. The STP instance is removed when the last interface is moved to another VLAN. You can configure switch and port parameters before an STP instance is created. These parameters are applied when the STP instance is created. You can change all VLANs on a switch by using the stp-list parameter when you enter STP commands through the CLI. For more information, refer to the Catalyst 2900 Series XL and Catalyst 3500 Series XL Command Reference.

The Catalyst 2912 XL, Catalyst 2924 XL, and Catalyst 2924C XL support only 64 STP instances and 64 VLANs. All other Catalyst 2900 XL switches and all Catalyst 3500 XL switches support 64 STP instances and 250 VLANs.

Each VLAN is a separate STP instance. If you have already used up all available STP instances on a switch, adding another VLAN anywhere in the VLAN Trunking Protocol (VTP) domain creates a VLAN that is not running STP on that switch. For example, if 250 VLANs are defined in the VTP domain, you can enable STP on 64 of those VLANs. The remaining VLANs must operate with STP disabled.

You can disable STP on one of the VLANs where it is running, and then enable it on the VLAN where you want it to run. Use the no spanning-tree vlan vlan-id global configuration command to disable STP on a specific VLAN, and use the spanning-tree vlan vlan-id global configuration command to enable STP on the desired VLAN.

For more information about VLANs, see "Configuring VLANs."

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Re: 5505 stuck in VTP transparent

Unfortunatly/fortunatly the 5505s are on their way out, which is why they are not in a server role. Just getting some last use out of them for the next several months. The 2924s do only support 64 STP instances, but that is not the current problem(I've had to deal with that issue plenty already). The combination of 2924s and 2950s makes for some creative hand done prunning, but that shouldnt effect VTP mode. The 5505 is stuck in transpartent mode, and a 2924M should be able to be the VTP server with only STP instances as the issue.

I appreciate you suggestion, but for various internal reasons the 5505s can't be used as servers. I would just like to fix the current setup so the 5505 will work as it should.

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