Hi Jon The Module I am trying to change the MTU on is a WS-X6724-SFP 24 port Gigabit Ethernet SFP and I was trying to change the MTU value to 1000 on a number of interfaces on this blade. The default MTU value on each interface is 1500. GigabitEthernet1/16 is up, line protocol is up (connected)   Hardware is C6k 1000Mb 802.3, address is 0011.5cdd.ac63 (bia 0011.5cdd.ac63)   Description: AXD-20-03 lmijtn   MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec, When I go into interface configuration mode and run the command "mtu ?" this is the output shown IEBHCATE1(config)#int g1/16 IEBHCATE1(config-if)#mtu ?   <9216-9216>  MTU size in bytes IEBHCATE1(config-if)#mtu Which leads me to believe that I can only change the MTU value to 9216 bytes. Uttam: As this is a live port I cannot simply set it back to defaults. I would need to get a downtime window first. I was hoping that the MTU value was something that could be set on the fly. What I have managed to do is set theMTU value on the VLANs that these ports are associated with to 1000 bytes, and I am waiting to hear back from the troubleshooters whether this is sufficient for their requirements. Best Regards & Thanks for the responses. Michael ... View more

Hi Guiseppe I have not managed to get both GRE tunnels up and working at the same time. What is happening is that I start of with the two routers (Jakarta & Kalimantan) configured with a WAN link. These two routers are connected to a third router acting as the Internet. I can ping the WAN interface on each router from the other. I then configured the 2 VRF's on each router SI , RD 100:1 EDU RD 200: Next I create the tun0 interface one each router. Assign it to the SI VRF with the command "ip vrf forwarding SI". I then assign an IP address to the tun0 interfaces on each router. These IP addresses are in the same /24 subnet. I then configure the tunnel source, which is the F0/0 (WAN) interface on the local router and the destination IP address, which is the IP address assigned to the WAN interface of the other router. I set the tunnel mode to "gre ip". At this stage I can ping the opposite routers tunnel end point IP address from each router. All is good. The problem arises then when I configure the tun1 interfaces. Same procedure as above, only this interface is assigned to the VRF EDU and the IP addresses assigned to the tun1 interfaces on each router are in a different subnet to that used on tun0. And like tun0, the IP addresses used on both tun1 interfaces belong to the same /24 subnet. The source and destination information is identical to that used on tun0 and again the mode is set to "gre ip". So now I try my pings again, and I can ping the tun1 end point IP addresses from the opposite router. However I can no longer ping the tun0 end point IP addresses. I have done some googling and found a post were someone mentioned using tunnel keys on the end points, and I tried this also. I gave both tun0 interfaces the key 1 and both tun1 interfaces the key of 2, but I could still only ping the end point IP addresses of tun1 from the opposite router.It was still not possible to ping the tun0 end point IP addresses. All I got was 5 periods (.....) indication a filed attempt. I have also tried using loopback interfaces as the tunnel source and destination addresses, but with this configuration I could not get even 1 tunnel up and working. Google is giving me lots of documents on setting up GRE or setting up VRF's, but so far not much at all on what I am trying to do Can I ask are there any special considerations to take into account when settign up 2 GRE tunnels with a single VRF assigned to each tunnel? Again thanks a million for yoru replies and help with this. Best Regards, Michael ... View more

Hi All I think I am making slow but steady progress. I have configured two tunnel interfaces Tun0 & Tun1 and these are bound to two different VRF's. Tun0 is bound ot vrf SI and Tun1 is bound ot vrf EDU. However I can only ping the tunnel end point of tun0. I have tried first with both tunnels using the same source port and Dest IP address. Then I tried adding a secondary IP address to my WAN interface of both routers and having Tun1 use tha local secondary IP as its source and the remote secondary IP as teh dest, but still I only have connectivity over Tun0. Not too sure if this is something that I have done incorrectly or if this is a bug/problem with GRE on Dynamips. Tunnel Configurations JAKARTA interface Tunnel0 ip vrf forwarding SI ip address 10.0.0.1 255.255.255.0 tunnel source 192.168.50.1 tunnel destination 192.168.80.1 ! interface Tunnel1 ip vrf forwarding EDU ip address 20.0.0.1 255.255.255.0 tunnel source 192.168.51.1 tunnel destination 192.168.81.1 ! interface FastEthernet0/0 ip address 192.168.51.1 255.255.255.0 secondary ip address 192.168.50.1 255.255.255.0 duplex auto speed auto KALIMANTAN interface Tunnel0 ip vrf forwarding SI ip address 10.0.0.2 255.255.255.0 tunnel source 192.168.80.1 tunnel destination 192.168.50.1 ! interface Tunnel1 ip vrf forwarding EDU ip address 20.0.0.2 255.255.255.0 tunnel source 192.168.81.1 tunnel destination 192.168.51.1 ! interface FastEthernet0/0 ip address 192.168.81.1 255.255.255.0 secondary ip address 192.168.80.1 255.255.255.0 duplex auto speed auto If anybody has any ideas it would be much appreciated. Best Regards, Michael ... View more

Hi Reza Thank you for your response and the example configuration. Is it not possible to send VRF traffic over a GRE tunnel without using a routing protocol. Just using static routes? Best Regards, Michael ... View more

Hi Guiseppe Again many thanks for your reply. Working with VRF's for the first time is kind of confusing So I have reconfigured the routers just for VRF SI initially and now I that I know the correct commands to use, I can see that there is an entry for the SI vrf (see below) JAKARTA# sh ip route vrf SI Gateway of last resort is not set      10.0.0.0/24 is subnetted, 1 subnets C       10.0.0.0 is directly connected, Tunnel0 KALIMANTAN#sh ip route vrf SI Gateway of last resort is not set      10.0.0.0/24 is subnetted, 1 subnets C       10.0.0.0 is directly connected, Tunnel0 and both Tunnel interfaces are "UP UP" Should I be able to ping the tunnel end points with the command ping vrf SI 10.0.0.x from each router? as when I try this the ping fails. Sorry for all the questions and again thanks a million for you help and advice. Best Regards, Michael ... View more

Hi Giuseppe Thanks for the reply. I have tried this and it's sill not working. What I have done is Removed the "ip vrf forwarding SI/EDU" commands from F2/0 7 F2/1 from both routers This removed the IP addresses on these interfaces automatically I then shut down both F2/0 7 F2/1 on both routers Next I configured the Tun0 interfaces as follows I added the "ip vrf forwarding SI/EDU" command to the tun0 interface on each router This removed the 10.0.0.x IP addresses I had previously assigned I then configued the IP address 159.xxx.10.1 on the tun0 interface on the JAKARTA router I then configured the IP address 159.xxx.100.1 on the tun0 interface on the KALIMANTAN router Next I removed and reconfigured the tunnel source & tunnel dest statemetns on the tun0 interface on each router Tunnel config from "show run" command on JAKARTA interface Tunnel0 ip vrf forwarding SI ip address 159.107.178.1 255.255.255.0 tunnel source 192.168.50.1  --> IP address on interface F0/0 (WAN Interface) tunnel destination 192.168.80.1 --> IP address on F0/0 (WAN Interface) on KALIMANTAN Tunnel config from "show run" command on KALIMANTAN interface Tunnel0 ip vrf forwarding SI ip address 159.107.212.1 255.255.255.0 tunnel source 192.168.80.1 --> IP Address on Interface F0/0 (WAN Interface) tunnel destination 192.168.50.1 --> IP Address on interface F0/0 (WAN Interface) on JAKARTA From JAKARTA I then tried to ping 159.xxx.100.1, but this was not successful and likewise pinging 159.xxx.10.1 from KALIMANTAN was unsuccessful. I expected to see entries in the routing table for the tunnel0 interface but this is not the case (See below) JAKARTA Gateway of last resort is 192.168.50.2 to network 0.0.0.0 C    192.168.50.0/24 is directly connected, FastEthernet0/0 S*   0.0.0.0/0 [1/0] via 192.168.50.2 KALIMANTAN Gateway of last resort is 192.168.80.2 to network 0.0.0.0 C    192.168.80.0/24 is directly connected, FastEthernet0/0 S*   0.0.0.0/0 [1/0] via 192.168.80.2 I have attached the full configuration from each router to this post. FYI I am using Dynamips, simulating 3 7206VXR routers, each running  7200 Software (C7200-P-M), Version 12.3(2)T1,  RELEASE SOFTWARE (fc2) Full output from "show ver" command below KALIMANTAN#sh ver Cisco Internetwork Operating System Software IOS (tm) 7200 Software (C7200-P-M), Version 12.3(2)T1,  RELEASE SOFTWARE (fc2) Synched to technology version 12.3(1.9) TAC Support: http://www.cisco.com/tac Copyright (c) 1986-2003 by cisco Systems, Inc. Compiled Fri 22-Aug-03 20:34 by dchih Image text-base: 0x60008954, data-base: 0x61AEE000 ROM: ROMMON Emulation Microcode BOOTLDR: 7200 Software (C7200-P-M), Version 12.3(2)T1,  RELEASE SOFTWARE (fc2) KALIMANTAN uptime is 3 hours, 20 minutes System returned to ROM by unknown reload cause - suspect boot_data[BOOT_COUNT] 0x0, BOOT_COUNT 0, BOOTDATA 19 System image file is "t ftp://255.255.255.255/unknown " cisco 7206VXR (NPE400) processor (revision A) with 245760K/16384K bytes of memory. Processor board ID 4294967295 R7000 CPU at 150Mhz, Implementation 39, Rev 2.1, 256KB L2, 512KB L3 Cache 6 slot VXR midplane, Version 2.1 Last reset from power-on X.25 software, Version 3.0.0. Bridging software. PCI bus mb0_mb1 has 400 bandwidth points PCI bus mb2 has 400 bandwidth points 4 FastEthernet/IEEE 802.3 interface(s) 8 Serial network interface(s) 125K bytes of non-volatile configuration memory. 65536K bytes of ATA PCMCIA card at slot 0 (Sector size 512 bytes). 8192K bytes of Flash internal SIMM (Sector size 256K). Configuration register is 0x2142 KALIMANTAN# Again if you could give me an idea of where I have gone wrong it would be much appreciated. Best Regards, Michael ... View more

Hi There Thank you for taking the time to read my question and respond. At present there is no TACACS+/AAA configured. In our group there was 1 or 2 folks who worked on these nodes and documented any changes they made. However now that our customer is to have access to these nodes and even though that have been tols that the must also log all changes they make, we just want to see if there is any way that we can track their activity on these nodes to ensure that we know exactly what they are doing as all connectivity/routing problems will still end up with us and will be difficult to work through if we can not be sure what changes have been made. As I said we would like to record when a customer logs onto one of these nodes what changes they make. The auto action for syslog look interesting. will look into this Best Regards, Michael ... View more