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can't ping or telnet to or from a cat 3550

I am having a problem with a cat 3550 running IOS 12.1(9). The switch seems to be switching and routing just fine but I can't seem to ping to it or from it. I cannot telnet to it or do anything to remotely administer it. I have noticed that when I try to ping another host from the switch, the other host is sending out replies but for whatever reason, the switch isn't recognizing them as the ping command reports no reply (ie: ..... - not the !!!!!) I can see that both the switch and the host have the correct mac address in their arp cache.

I do not have any access lists configured. I have recently made a change to vlans and routing but I have checked over those changes more than once. In addition, I wouldn't suspect the routing anyway since I'm trying to ping it from a connected subnet. One thing I did notice is that 'Administrative Mode' is set to static access:

#show int switchport Name: Fa0/1 Switchport: Enabled Administrative Mode: static access Operational Mode: static access Administrative Trunking Encapsulation: negotiate Operational Trunking Encapsulation: native Negotiation of Trunking: Off Access Mode VLAN: 2 Trunking Native Mode VLAN: 1 (default) Trunking VLANs Enabled: ALL Pruning VLANs Enabled: 2-1001

Protected: false Unknown unicast blocked: disabled Unknown multicast blocked: disabled

Could this be the cause of my problem? If so, how would you fix that? Do these switches have any way of configuring the management Vlan?

Thanks!

Here is my sanatized config for reference:

---------------------------------------------------------------------------------------------- switch3550a#show run Building configuration...

version 12.1 no service pad service password-encryption ! hostname switch3550a !

! ip subnet-zero ip routing no ip domain-lookup ip name-server 192.168.4.24 ! vtp mode transparent ! vlan 2 name xxxx2 ! vlan 3 name xxxx3 ! vlan 4 name xxxx4 ! vlan 5 name xxxx5 ! vlan 6 name xxxx6 ! vlan 7 name xxxx7 ! vlan 8 name xxxx8 ! vlan 9 name xxxx9 ! vlan 10 name xxxx10 ! vlan 11 name xxxx11 ! spanning-tree extend system-id ! ! ! interface FastEthernet0/1 switchport access vlan 2 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/2 switchport access vlan 3 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/3 switchport access vlan 8 switchport mode access no ip address duplex full speed 100 ! !\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ !output supressed (all ports are configured the same way with only the vlan changing per interface !VLAN 1 is not configured on a connected port !////////////////////////////////////////////////////////////////////////////////////////////////// ! ! ! interface Vlan1 no ip address spanning-tree portfast ! interface Vlan2 ip address 192.168.3.66 255.255.255.248 ! interface Vlan3 ip address 192.168.3.74 255.255.255.248 ! interface Vlan4 ip address 192.168.6.161 255.255.255.240 ! interface Vlan5 ip address 192.168.5.1 255.255.255.240 ! interface Vlan6 no ip address ! interface Vlan7 no ip address ! interface Vlan8 no ip address ! interface Vlan9 ip address 192.168.34.46 255.255.255.240 ! interface Vlan10 no ip address ! interface Vlan11 no ip address ! ip classless ip route 0.0.0.0 0.0.0.0 192.168.3.65 ip route 0.0.0.0 0.0.0.0 192.168.3.73 50 no ip http server ! ! ! ! line con 0 exec-timeout 0 0 logging synchronous line vty 0 4 exec-timeout 45 0 password 7 xxxxxxxxxxxx logging synchronous login line vty 5 15 logging synchronous login ! ntp clock-period 17180020 ntp server 192.168.34.3 end

Reply to
zarmice
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Any suggestions on this? I have been trying to figure this out for days and have not found an answer. Any help is appreciated.

zarmice

Reply to
zarmice

What have you already done to try and fix it?

Reply to
Dana

That would seem unusual.

To troubleshoot the coms you need to detail where you are pinging from, the IP address/mask of the source, the target address. To start.

If all other communications is working I guess it could be the box.

Is logging enabled?

post sh log ! anything interesting? sh mem ! first few lines

Reply to
Bod43

Logging is enabled but shows nothing at all other than a couple interfaces going down and up again but wouldn't be related to this as they occured a few days ago and the interfaces are up/up now anyway:

#show log Syslog logging: enabled (0 messages dropped, 0 flushes, 0 overruns) Console logging: level debugging, 64331 messages logged Monitor logging: level debugging, 3 messages logged Buffer logging: level debugging, 64331 messages logged File logging: disabled Trap logging: level debugging, 64335 message lines logged Logging to 65.220.38.82, 64245 message lines logged

Log Buffer (4096 bytes): down .Sep 11 16:56:33.164 est: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/18, changed state to down .Sep 11 16:57:40.681 est: %LINK-3-UPDOWN: Interface FastEthernet0/18, changed state to up .Sep 11 16:57:41.681 est: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/18, changed state to up .Sep 11 16:57:41.961 est: %LINK-3-UPDOWN: Interface FastEthernet0/10, changed state to up .Sep 11 16:57:42.081 est: %LINK-3-UPDOWN: Interface FastEthernet0/12, changed state to up .Sep 11 16:57:42.961 est: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/10, changed state to up .Sep 11 16:57:43.081 est: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/12, changed state to up

I am trying to ping from a host on Vlan 9, 192.168.34.44. This ping is initiated on the switch itself. I have also tried pinging the host from the switch which also does not work. The host has the same subnet as the switch, 255.255.255.240. I've verified the host is on an interface that is set up in Vlan 9 with switchport access vlan9 and switchport mode access. Both host and switch have the correct duplex and speed (100, full). This host is on interface fa 0/9:

interface FastEthernet0/9 switchport access vlan 9 switchport mode access no ip address duplex full speed 100

There are no access lists on the host that would prevent it from replying, in fact, I do see replys coming from the host using tcpdump on the host.

I have tried a similar test on one of the other Vlans. Same configuration except for the ip addresses and Vlan number. I had the same problem. I cannot ping anywhere from the switch itself either.

A show mem gives this output:

#show mem Head Total(b) Used(b) Free(b) Lowest(b) Largest(b) Processor 9E4A0C 56724980 4654060 52070920 51102188

51800768 I/O 80000000 8388608 936436 7452172 7202332 7384300

Processor memory

Address Bytes Prev Next Ref PrevF NextF Alloc PC what

009E4A0C 0000001504 00000000 009E5018 001 ------- ------- 0018E6E8 List Elements 009E5018 0000005004 009E4A0C 009E63D0 001 ------- ------- 0018E718 List Headers 009E63D0 0000009000 009E5018 009E8724 001 ------- ------- 001A7FB8 Interrupt Stack . . .

Thanks!

Reply to
zarmice

conf t no logging console logging buffer 10000 debug end wri mem

clear logging

Post the output of the following:

sh version

sh ip int brief sh int status sh vlan

sh int vlan 9

ping 192.168.34.46

debug icmp debug arp

ping 192.168.34.255

sh arp

sh logging

Reply to
Merv

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