topic Re: InterVLAN routing in Routing and SD-WAN

InterVLAN routing

DavitiAbesalashvili — Sat, 18 Apr 2020 22:55:55 GMT

Hello. I have been practicing in interVLAN routing and faced trouble.

I have GNS3 and my topology looks like this:

Device MY_PC is cloud connected to virtual interface on my PC. I can ping gateway subinterface of all subnets. Although I can ping PC2 from PC1. Can ping VLAN 10 from my pc (using CMD) and gateway but not other devices or even router subinterfaces.

Here are configurations:

Router:

Current configuration : 1331 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
ip cef
!
!
!
!
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
!
interface FastEthernet0/1.10
encapsulation dot1Q 10
ip address 192.168.10.254 255.255.255.0
!
interface FastEthernet0/1.20
encapsulation dot1Q 20
ip address 192.168.20.254 255.255.255.0
ip helper-address 192.168.40.1
!
interface FastEthernet0/1.30
encapsulation dot1Q 30
ip address 192.168.30.254 255.255.255.0
ip helper-address 192.168.40.1
!
interface FastEthernet0/1.40
encapsulation dot1Q 40
ip address 192.168.40.254 255.255.255.0
!
interface FastEthernet1/0
no ip address
shutdown
duplex auto
speed auto
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
no cdp log mismatch duplex
!
!
!
!
control-plane
!
!
!
!
!
!
!
!
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
!
end

Switch:

Current configuration : 1795 bytes
!
! Last configuration change at 22:40:09 UTC Sat Apr 18 2020
!
version 15.2
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
service compress-config
!
hostname SW1
!
boot-start-marker
boot-end-marker
!
!
logging discriminator EXCESS severity drops 6 msg-body drops EXCESSCOLL
logging buffered 50000
logging console discriminator EXCESS
!
no aaa new-model
!
!
!
!
!
no ip icmp rate-limit unreachable
!
!
!
no ip domain-lookup
ip cef
no ipv6 cef
!
!
!
spanning-tree mode rapid-pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
ip tcp synwait-time 5
!
!
!
!
!
!
!
!
!
!
!
!
!
interface Ethernet0/0
switchport trunk allowed vlan 10,20,30,40
switchport trunk encapsulation dot1q
switchport trunk native vlan 99
switchport mode trunk
!
interface Ethernet0/1
switchport access vlan 10
switchport mode access
!
interface Ethernet0/2
switchport access vlan 20
switchport mode access
!
interface Ethernet0/3
switchport access vlan 30
switchport mode access
!
interface Ethernet1/0
switchport access vlan 40
switchport mode access
!
interface Ethernet1/1
!
interface Ethernet1/2
!
interface Ethernet1/3
!
interface Ethernet2/0
!
interface Ethernet2/1
!
interface Ethernet2/2
!
interface Ethernet2/3
!
interface Ethernet3/0
!
interface Ethernet3/1
!
interface Ethernet3/2
!
interface Ethernet3/3
!
interface Vlan1
no ip address
shutdown
!
interface Vlan10
ip address 192.168.10.253 255.255.255.0
!
ip default-gateway 192.168.10.254
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
!
!
!
!
control-plane
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
!
end

Re: InterVLAN routing

Martin L — Sat, 18 Apr 2020 23:06:05 GMT

What is MY_PC default gateway? is it Router's IP of 192.168.10.254?

Re: InterVLAN routing

DavitiAbesalashvili — Sat, 18 Apr 2020 23:52:01 GMT

Here is output of ipconfig and pinging default gateway of MY_PCs subnet and default gateway of another subnet.

Re: InterVLAN routing

luis_cordova — Sun, 19 Apr 2020 00:22:57 GMT

Hi @DavitiAbesalashvili

Occasionally, PC firewalls block pinging of external networks.
Check that the firewall of your S.O. it is not blocking the ping.

Regards

Re: InterVLAN routing

Martin L — Sun, 19 Apr 2020 00:59:53 GMT

I see you are using VMNet10 as a connection to your GNS3 Cloud but not Microsoft Loopback interface. In the past, I always use MS Loopback interface to connect to GNS3 and were able to ping GNS3 device via CMD of my Host PC.
Please check GNS3 doc or forums which way you should use it. I think only way is via MS Loop and not via VMnet.

Regards, ML
**Please Rate All Helpful Responses **

Re: InterVLAN routing

Martin L — Sun, 19 Apr 2020 01:01:47 GMT

briefly disabling PC firewall during testing is good idea

Re: InterVLAN routing

RaviM — Sun, 19 Apr 2020 01:12:43 GMT

Can you share route print from your machine? And try doing capture on your pc and start a ping from router.

Re: InterVLAN routing

DavitiAbesalashvili — Sun, 19 Apr 2020 10:36:59 GMT

That are results with disabled firewall.

Re: InterVLAN routing

DavitiAbesalashvili — Sun, 19 Apr 2020 10:37:36 GMT

That are results with disabled firewall.

Re: InterVLAN routing

paul driver — Sun, 19 Apr 2020 11:52:06 GMT

Hello

You a missing the native vlan on the router, by default the physical interface of the subinterfaces would be it (vlan 1) but as you have stated a native vlan 99 you need to create this on your router

RTR
conf t

int fa0/1.99
encapsulation dot1Q 99 native

Re: InterVLAN routing

DavitiAbesalashvili — Sun, 19 Apr 2020 16:44:38 GMT

Changed VMware virtual interface to MS loopback and have same issue. can ping router;s subinterface in my subnet but not another one. When I change it to VPC I can ping everything. Guess something is wrong with interaction between MS and GNS3

Re: InterVLAN routing

Vishnu Vardhan S — Sun, 19 Apr 2020 17:20:57 GMT

Use a native vlan dot1q on the router and check if that works.

Try using a normal PC instead of cloud and check if the ping works.

Re: InterVLAN routing

Martin L — Sun, 19 Apr 2020 18:44:33 GMT

did you disable Firewall on Host PC for testing? if still fails; save and exit. Create new project with MS Loop to Cloud to GNS3 Router without IOU switch.

Check GNS3 forums for help. Things might be different if you use GNS3 Server.

Regards, ML
**Please Rate All Helpful Responses **

Re: InterVLAN routing

DavitiAbesalashvili — Tue, 21 Apr 2020 01:10:27 GMT

Yes, firewall was disabled, tried config changes, advised here, and Vmware forum is quiet, couldn't figure out thing. Same works with use of VPCs.