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New Member

Switch Lost external connection

Please help. Switch Lost Internet connection, all computers have no internet. Here is what happened:

Correcting Interface Speeds. No problems

Then I started typing the following

"gi0\1" then stop and thought what am I going. then ctrlZ out of Config-if next thing I know everything went down and I started to get alerts.

Internal machines can talk to each other, but can not go outside. what have I done? What can I do to trouble shoot?

13 REPLIES

Re: Switch Lost external connection

Typing in g0/1 wouldn't have taken the switch down. It's very likely setting the speed may have caused this issue. If you hard-coded the speed then set the speed back to auto or if you set it to auto then set the speed back to whatever it was before. Did you set the speed on the uplink port that connects the LAN to the Internet?

HTH

Sundar

New Member

Re: Switch Lost external connection

On this switch nothing had been changed.

I went to "show int status"

saw that all interfaces were set to 100/full

Is there a command log that can show me everything that was entered or changed?

whats the best way to troubleshoot this issue?

Re: Switch Lost external connection

If the console session you used to enter the commands is still up you can do 'show history' and that would show the last 20 days commands typed. The other way you can find that information is if you have AAA setup for accounting to log console activity.

New Member

Re: Switch Lost external connection

Unfortunitly I don't have it up anymore thats why I was hoping that there were some logs, like the history command. So what else can I do to trouble shoot this, and find out why or what caused the connection to go down. I need to get this back UP ASAP.

Re: Switch Lost external connection

How does the switch connect to the Internet?

Can you ping the next hop for the default route?

If you are still having problems can you post a sanitized copy of the switch configuration and explain your setup.

New Member

Re: Switch Lost external connection

I can't ping anywhere. I know it's not the router, beacuse there are two other switches there, and they work find. This is a for DR site. So I have two swithes. One in the CommRoom, which is connected to another by fiber, and that one connects to the Router.Thats LAN1 the other is LAN2. Both switches have 24 ports, with two fiber interfaces which are GI0/1 and GI0/2. GI0/2 is not connected. Now that I am thinking of it, when I was working on LAN1 and I said that I just started Typing GI0/1 I might of started also typing Speed. Could I have screwed up that up some how. When I show int status the GI0/1 port reads a-1000 a-full, for which it should. By starting the speed change and not completeing it, could it of changed something but still show up as not changed?

New Member

Re: Switch Lost external connection

What I didn't explain is that they are also trunking. There is only one vlan on each switch

Re: Switch Lost external connection

Assuming nothing might have changed other than the speed I would suggest you to configure the speed and duplex to auto on g0/1 port and let auto negotiation choose the speed/duplex. Are these layer 3 or layer 2 switches. If it's layer 2 switch can you try pinging the default gateway set on the switch? Also, can you do a clear counters and do a show int g0/1 and check whether you are seeing 2-way traffic.

HTH

Sundar

New Member

Re: Switch Lost external connection

I just tried pinging the Default gateway about 5 minutes ago, and nothing. I compared the cnfigs and nothing has changed there either.

New Member

Re: Switch Lost external connection

Here is what I have. GI0/1 is showing up. Look at the following:

GigabitEthernet0/1 is up, line protocol is up (connected)

Hardware is Gigabit Ethernet, address is (Sensored)

MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Full-duplex, 1000Mb/s, media type is SX

input flow-control is off, output flow-control is off

ARP type: ARPA, ARP Timeout 04:00:00

Last input 00:00:05, output 00:00:00, output hang never

Last clearing of "show interface" counters never

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 1000 bits/sec, 1 packets/sec

5 minute output rate 1000 bits/sec, 2 packets/sec

13712 packets input, 2499779 bytes, 0 no buffer

Received 2675 broadcasts (0 multicast)

0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog, 884 multicast, 0 pause input

0 input packets with dribble condition detected

30608 packets output, 3202633 bytes, 0 underruns

Fa0/4 notconnect 1 full 100 10/100BaseTX

Fa0/5 connected 1 full 100 10/100BaseTX

Fa0/6 connected 1 full 100 10/100BaseTX

Fa0/7 notconnect 1 full 100 10/100BaseTX

Fa0/8 notconnect 1 full 100 10/100BaseTX

Fa0/9 notconnect 1 full 100 10/100BaseTX

Fa0/10 notconnect 1 full 100 10/100BaseTX

Fa0/11 notconnect 1 full 100 10/100BaseTX

Fa0/12 notconnect 1 full 100 10/100BaseTX

Fa0/13 notconnect 1 full 100 10/100BaseTX

Fa0/14 notconnect 1 full 100 10/100BaseTX

Fa0/15 notconnect 1 full 100 10/100BaseTX

Fa0/16 notconnect 1 full 100 10/100BaseTX

Fa0/17 notconnect 1 full 100 10/100BaseTX

Fa0/18 notconnect 1 full 100 10/100BaseTX

Fa0/19 notconnect 1 full 100 10/100BaseTX

Fa0/20 notconnect 1 full 100 10/100BaseTX

Fa0/21 notconnect 1 full 100 10/100BaseTX

Fa0/22 notconnect 1 full 100 10/100BaseTX

Fa0/23 notconnect 1 full 100 10/100BaseTX

Fa0/24 notconnect 1 full 100 10/100BaseTX

Gi0/1 connected trunk a-full a-1000 1000BaseSX

Gi0/2 notconnect 1 auto auto 1000BaseSX

Re: Switch Lost external connection

Is g0/1 a trunk port. If it is make sure the trunk configuration is identical on both ends of the link. Posting the configuration, after removing any sensitive info, would help isolate the problem much quicker.

New Member

Re: Switch Lost external connection

how do I check the Trunk configuration? I am not familar with trunking. There was never a problem with it before? I know I didn't change anything, well at least I am sure that I didn't. Let me know

New Member

Re: Switch Lost external connection

hi, better post the running config and remove any public IP if there is...

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