The first thing that sticks out to me, is that on the 7024P the VLAN 30 IP address is in the same subnet as  VLAN 10 IP addresses on the other switches. This creates a scenario on the Cisco and 8024 switches, where you cannot assign a 192.168.10.x IP address to VLAN 30. Because VLAN 30 does not have an IP address, it cannot be routed. This results in the 7024 forwarding VLAN 30 tagged traffic on port Gi1/0/12. The CISCO_3750G receives this tagged traffic for VLAN 30, but then cannot do anything with it.  There are a couple approaches to resolving this. You could assign a different subnet to VLAN 30. Then on each switch assign an IP address to VLAN 30. On your CISCO_3750G configure the switch for VLAN routing.  [URL] Another option would be to not use VLAN 30. Instead use VLAN 10 on the 7024 and assign VLAN 10 the 192.168.10.91 IP address.  Once you have the IP scheme straitened out, then I would proceed with fine tuning the spanning tree instances.  Here is a white paper with some helpful best practices and examples of MSTP use.  [URL] Cheers
Hi all,  I'm a beginner engineer, so I have a little knowledge. I tried to configure by myself, but some problem was bothering me.. I want you guys to help me!!   Actually I configured MSTP using the 4 switches(CISCO&DELL). Please show the attachment pictured and configuring file(.txt) ( I draw it and scanned..) As you can see the picture, you'll know what I want to configure.   The point I want is following contents. (855) 935-7526 ***. I want to communicate with whole switches. => but, Dell 7024P does not communicate any other switches.. I think assigning IP is vlan 30(192,168.10.91) ... others have vlan 10(192.168.10.x) Actually, It was very big issue.   2. Only Dell 7024P does not communicate with Internet.   So, I configured whole switches static routing (ip route 0.0.0.0 0.0.0.0 192.168.10.94) But only 7024P does not communicate..   In order to connect each other, what can I do in the Dell 7024P switch. Thank you Daniel C.  [View:/cfs-file/__key/communityserver-discussions-components-files/866/CISCO3560-show-run_2C00_-stp.txt:550:0] [View:/cfs-file/__key/communityserver-discussions-components-files/866/CISCO3750-show-run_2C00_-stp.txt:550:0] [View:/cfs-file/__key/communityserver-discussions-components-files/866/DELL7024P-show-run_2C00_-stp.txt:550:0] [View:/cfs-file/__key/communityserver-discussions-components-files/866/DELL8024F-show-run_2C00_-stp.txt:550:0] [IMAGE]
Communicating different VLAN using MSTP.