VLAN problem/missing ??

[shahid_duet]

I m using all cisco switch in my network. See my diagram.

My configurations are here:

Router : 3845

int F 0/0/1

ip add     192.168.0.252/24

int F 0/0/1.2

encaptulation dot1lQ 15

ip address 192.168.3.252/24

Core Switch 4507

interface GigabitEthernet3/1

switchport trunk encapsulation dot1q

switchport mode trunk

!

interface GigabitEthernet3/2

switchport trunk encapsulation dot1q

switchport mode trunk

interface Vlan15

ip address 192.168.3.250 255.255.255.0

!

interface Vlan20

ip address 192.168.0.250 255.255.255.0

ip route 0.0.0.0 0.0.0.0 192.168.0.252

Assess Switch 2960

interface FastEthernet0/1

switchport mode trunk

!

interface FastEthernet0/2

switchport access vlan 20

!

interface FastEthernet0/3

switchport access vlan 15

interface Vlan15

ip address 192.168.3.98 255.255.255.0

no ip route-cache

!

interface Vlan20

ip address 192.168.0.98 255.255.255.0

no ip route-cache

!

ip default-gateway 192.168.0.254

When i access my server( 192.168.10.10) from 192.168.0.14 its faster and ping latency always 1 ms.

When i access my server( 192.168.10.10) from 192.168.3.14 its lower and ping latency sometime 100,200,350,1,1,1, ms etc.

whats my mistake and how i access faster from 192.168.3.14.

Please help Me.

Shahid

[kcnajaf · Accepted solution]

Hi Shahid,

For some reason the configuration you have provided above does not match with the diagram specifically for acces vlans and trunk ports.

Also it looks like you have ip address assigned to physical interface as well as subinterface? Can these IP's be assigned both to sub interface and encapsulate with correct vlan numbers (20 and 15)???

If i was you i will follow below steps to isolate the problem.

1) Verify if there is any errors on the port where 192.168.3.14 is connected.

2) If this port is configured with speed and duplex to autonegotiate, hardcore this manually both on switch end and on PC end as well.

3) Verify how the spanning tree path for VLAN 15 and comapre it with VLAN 20.

4) Try pinging between the PC's to verify if you see the performance difference like what you see to Server.

5) Verify if there are any errors on the trunk links from access switch all the way till router.

Hope this helps.

Regards

Please rate when applicable or helpful !!!

[shahid_duet]

Hi Najaf

What is the mismatch ?? 

pls tell me. i am finding that

[kcnajaf]

Hi,

So you want me to tell this rather than you finding it yourself :-)

Fair enough here it goes.

Accoring the above configuration you have shared for the access switch 2960.

Fas 0/1 - Trunk

Fas 0/2 - Vlan 20

Fas 0/3 - Vlan 15

But in your diagram

Fas 0/1 - Vlan 20

Fas 0/2 - Vlan 15

Fas 0/3 - Vlan 20

Fas 0/4 - Vlan 15

Hope now you get that.

Regards

Najaf

[shahid_duet]

hi najaf

yes i have mismatch.Here configuration is corrct and mistake at diagram.

I did HSRP on router F 0/0/1 like

standby 4 priority 140

standby 4 preempt

standby 4 track GigabitEthernet0/1

If i want to change config f0/0/1 to f0/0/1.1 it says

%Must use unique HSRP group number for each logical interface

that is a member of the same physical interface.

But inf f0/0/1.2 dont have any HSRP.

Firstly

How i configure f0/0/1.1 with

ip add 192.168.0.252/24

standby 4 priority 140

standby 4 preempt

standby 4 track GigabitEthernet0/1

secondly, i am not clear ur suggestion # 3. pls descrive me.

Thanking YOu

shahid

[shahid_duet]

Mr. najaf

Yes, i got problem. when i changed f 0/0/1.2 configuration to another physical interface  its working and have no problem.

Is it possible to do HSRP at only one sub-interface ????

shahid

[kcnajaf]

Hi Shahid,

Glad to hear that your issue is resolved.

Do you have dual (pair of ) Core Switches?

There is no fun in running HSRP only on one interface. The purpose of HSRP is to provide first hope resiliency. If you configure it only on one device and if this goes down there is no fall back. So HSRP to work you need to configure them on two interface of seperate devices.

Hope you are getting my point.

Regards

Najaf

[shahid_duet]

Najaf

I have 2 switch and 2 router.

Now my situation stands i have to do HSRP between prinary router sub-interface and secondary router physical interface. prinary router another sub-interface need not do HSRP.

is it possible to do at sub-interface ?????

shahid

[kcnajaf]

Hi Shahid,

HSRP will work on Sub interface, as long as you have L2 path between the physical interface and subinterface. Still I was not able to figure out a practical schnerio why you would want to use this way :-)

Anyway you can give a try and it should work.

Regards

Najaf