# ADSL, ADSL 2, ADSL 2+  και  Broadband Hardware > Cisco  ADSL modems και routers >  Cannot Ping Between Vlan interfaces

## JohnF

Καλησπέρα , 

προσπαθώ να κάνω μια προσωμοίωση σε GNS3. H τοπολογία είναι η εξής και το config είναι πολύ απλό και είναι το εξής:



ALS1: 

```
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname ALS1
!
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 auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface Port-channel1
 switchport mode trunk
!
interface Port-channel3
 switchport mode trunk
!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/0
 no ip address
 shutdown
 clock rate 2000000
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/1
 no ip address
 shutdown
 clock rate 2000000
!
interface FastEthernet1/0
!
interface FastEthernet1/1
!
interface FastEthernet1/2
!
interface FastEthernet1/3
!
interface FastEthernet1/4
!
interface FastEthernet1/5
!
interface FastEthernet1/6
 switchport access vlan 100
!
interface FastEthernet1/7
 switchport mode trunk
 channel-group 1 mode on
!
interface FastEthernet1/8
 switchport mode trunk
 channel-group 1 mode on
!
interface FastEthernet1/9
!
interface FastEthernet1/10
!
interface FastEthernet1/11
 switchport mode trunk
 channel-group 3 mode on
!
interface FastEthernet1/12
 switchport mode trunk
 channel-group 3 mode on
!
interface FastEthernet1/13
!
interface FastEthernet1/14
!
interface FastEthernet1/15
!
interface Vlan1
 ip address 172.16.1.101 255.255.255.0
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
no cdp log mismatch duplex
!
!
!
!
control-plane
!
!
!
!
!
```

ALS2 :  

```
Building configuration...

Current configuration : 1920 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname ALS2
!
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 auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface Port-channel3
 switchport mode trunk
!
interface Port-channel2
 switchport mode trunk
!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/0
 no ip address
 shutdown
 clock rate 2000000
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/1
 no ip address
 shutdown
 clock rate 2000000
!
interface FastEthernet1/0
!
interface FastEthernet1/1
!
interface FastEthernet1/2
!
interface FastEthernet1/3
!
interface FastEthernet1/4
!
interface FastEthernet1/5
!
interface FastEthernet1/6
!
interface FastEthernet1/7
!
interface FastEthernet1/8
!
interface FastEthernet1/9
 switchport mode trunk
 channel-group 2 mode on
!
interface FastEthernet1/10
 switchport mode trunk
 channel-group 2 mode on
!
interface FastEthernet1/11
 switchport mode trunk
 channel-group 3 mode on
!
interface FastEthernet1/12
 switchport mode trunk
 channel-group 3 mode on
!
interface FastEthernet1/13
!
interface FastEthernet1/14
!
interface FastEthernet1/15
!
interface Vlan1
 ip address 172.16.1.102 255.255.255.0
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
mac-address-table static c203.0c0c.0000 interface FastEthernet1/9 vlan 1
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
```

DSW1 : 

```
Building configuration...

Current configuration : 2009 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname DSW1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
no ip cef
!
!
!
!
no ip domain lookup
ip auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface Port-channel1
 switchport mode trunk
!
interface Port-channel2
 switchport mode trunk
!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/0
 no ip address
 shutdown
 clock rate 2000000
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/1
 no ip address
 shutdown
 clock rate 2000000
!
interface FastEthernet1/0
!
interface FastEthernet1/1
!
interface FastEthernet1/2
!
interface FastEthernet1/3
!
interface FastEthernet1/4
!
interface FastEthernet1/5
!
interface FastEthernet1/6
!
interface FastEthernet1/7
 switchport mode trunk
 channel-group 1 mode on
!
interface FastEthernet1/8
 switchport mode trunk
 channel-group 1 mode on
!
interface FastEthernet1/9
 switchport mode trunk
 channel-group 2 mode on
!
interface FastEthernet1/10
 switchport mode trunk
 channel-group 2 mode on
!
interface FastEthernet1/11
!
interface FastEthernet1/12
!
interface FastEthernet1/13
!
interface FastEthernet1/14
!
interface FastEthernet1/15
!
interface Vlan1
 ip address 172.16.1.1 255.255.255.0
!
interface Vlan100
 ip address 172.16.100.1 255.255.255.0
!
interface Vlan200
 ip address 172.16.200.1 255.255.255.0
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
mac-address-table static c201.10bc.0000 interface FastEthernet1/8 vlan 1
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
```

To θέμα είναι πως δεν μπορώ να κάνω ping μεταξύ των management vlan interfaces (VLAN1 - 172.16.1.0/24) κάποιες φορες. Πχ δουλεύει το ping μεταξύ ALS1 και DSW1 αλλά όχι μεταξύ ALS1-ALS2 και ALS2-DSW1 ή το αντίθετο. Δουλεύει μεταξύ ALS2-DSW1 αλλά όχι ALS1-ALS2 και DSW1-ALS2. Aυτή την στιγμή συμβαίνει το 2ο.

Tα trunk links είναι οκ , το vtp  , cdp και το spanning tree δουλεύουν όπως αναμένεται.

Ping from ALS2 --> DLS1 :


```
ALS2#ping 172.16.1.1 source vlan 1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
Packet sent with a source address of 172.16.1.102

*Mar  1 03:25:33.839: IP: tableid=0, s=172.16.1.102 (local), d=172.16.1.1 (Vlan1), routed via RIB
*Mar  1 03:25:33.843: IP: s=172.16.1.102 (local), d=172.16.1.1 (Vlan1), len 100, sending
*Mar  1 03:25:33.843: IP ARP: creating incomplete entry for IP address: 172.16.1.1 interface Vlan1
*Mar  1 03:25:33.843: IP ARP: sent req src 172.16.1.102 c203.0c0c.0000,
                 dst 172.16.1.1 0000.0000.0000 Vlan1
*Mar  1 03:25:33.847: IP: s=172.16.1.102 (local), d=172.16.1.1 (Vlan1), len 100, encapsulation failed.

ALS2#sh arp
Protocol  Address          Age (min)  Hardware Addr   Type   Interface
Internet  172.16.1.102            -   c203.0c0c.0000  ARPA   Vlan1
```

Φαίνεται πως στέλνει ARP request αλλά δεν πέρνει απάντηση. Το περίεργο είναι πως το DSW1 φαίνεται να στέλνει ARP Reply!!



```
DSW1#
*Mar  1 03:25:33.863: IP ARP: rcvd req src 172.16.1.102 c203.0c0c.0000, dst 172.16.1.1 Vlan1
*Mar  1 03:25:33.863: IP ARP: sent rep src 172.16.1.1 c201.10bc.0000,
                 dst 172.16.1.102 c203.0c0c.0000 Vlan1
```

Eπίσης όταν συμβαίνει αυτό το sh adjacency vlan 1 δεν γυρνάει τπτ στο ΑLS ενώ στο DSW έχει κανονικά entries. Στα trunk links είναι allowed όλα τα vlans δεν έχω pruning.

Δοκίμασα να κάνω disable το CEF , τα ίδια. Απενεργοποίησα/Ενεργοποίησα IP routing στα ΑLS τα ίδια. Έσβησα τα etherchannels same . Eπίσης έσβησα το mac-address-table static entry που φαίνεται στο config ( το οποίο δεν ξέρω πως εμφανίστηκε αφού δεν είχα βάλει κανένα static entry).

Κάτι περίεργο παίζει με το CEF ή bug του IOS/GNS ?

Kαμιά ιδέα ? Έχω καιρό να ασχοληθώ με cisco και μου φαίνεται ενδιαφέρον  :Thinking: .

----------


## tsipoulanis

Μπορείς να στείλεις output των παρακατω εντολων?
show ip inter bri
show etherchannel summary

θα ήθελα να δω και ενα πλάνο σε layer 2 (spanning tree)
show spanning tree

----------


## net

Χωρίς να έχω δει τα config καλό θα είναι να κάνεις και ένα restart σε GNS/PC γιατί πολλές φορές είναι θέμα του GNS... θα δω και τo configuration αργότερα...

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## tsipoulanis

arxika, se fusiko epipedo einai ka8e switch me tous upoloipous 2 switch sundemenos. ara 8a eprepe na exoume Loops.
ara to STP 8a prepei na exei kapoia porta se blocking state.
aposundese ena UpLink metaksi 2 Switch kai pes mas an akomh xaneis pings.

sthn sunexeia opws eipe o filos parapanw, kane anazhthsh kai grafima na deis se logiko epipedo (gia ka8e sou vlan) pws einai to diktuo sou.

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