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Problem cisco 881 internet lost

Mohaax9999
Level 1
Level 1

Hello, 

I have a big problems with a cisco router 881,the connection works correctly when nobody use the networks(ping works on every computer) but when people working the connection gone every 5 minutes and comes back after 30 seconds

Please help me. 

thank you

14 Replies 14

blau grana
Level 7
Level 7

Hi,

Can you please let us know on which port is connected your LAN and WAN?

Also try this change and test if internet access is working:

no ip nat inside source list 2 interface FastEthernet0 overload
ip nat inside source list 2 interface FastEthernet4 overload
Best Regards Please rate all helpful posts and close solved questions

Hi,

Thank's for your answer  ! 

Wan is connected on port Wan  (FastEthernet 4)

and Lan on port F0

 

Why we need to put ip nat inside on the Wan ?

 

Thanks for your help

Hi,

ACL 2 tells you that packets which match this ACL will be NATed. State ment "interface Fa4 over" says that source address of match packets will be translated to IP address of this interface. You need to use Fa4 port because this port has public IP address.

Did this change help?

Best Regards Please rate all helpful posts and close solved questions

Thank's i will test that this afternoon  and where i set the ip nat outside ? Fa4 too ? 

 

 

please post another "show run" , a "show ip nat trans" , also what speed is your wan connection into fa4 ?

like i told this morning i found the problem it was the duplex it was in auto i set it on "full" and now the internet work like a charm ! no more collission thank's all !!

please post outputs of these commands:

 

sh run int Fa4

sh int Fa4

Best Regards Please rate all helpful posts and close solved questions

like i told this morning i found the problem it was the duplex it was in auto i set it on "full" and now the internet work like a charm ! no more collission thank's all !!

i have a lot tx_late_collision_err on Fa4 why ?

 

it is normal ?

 throttled=0, enabled=0, disabled=0
 rx_framing_err=0, rx_overflow_err=0, rx_buffer_err=0
 rx_no_enp=0, rx_discard=0, filtered_pak=0
 tx_one_col_err=25433, tx_more_col_err=13805, tx_deferred_err=128350
 tx_underrun_err=0, , tx_loss_carrier_err=3501
 tx_exc_collision_err=0, fatal_tx_err=1, tx_recovery_count=36
 fast_throttle_count=0, fast_unthrottle_count=0, max_pause_timeout=0

 

thanks

Aaron Ratcliffe
Level 1
Level 1
Yes Nat outside goes on the wan interface . the change advised above should correct your issue

i did it internet is ok but same thing every 5 minutes packet lost and connection back after 20-30 seconds 

 

Mohaax9999
Level 1
Level 1

i have a lot tx_late_collision_err on Fa4 why ?

 

it is normal ?

 throttled=0, enabled=0, disabled=0
 rx_framing_err=0, rx_overflow_err=0, rx_buffer_err=0
 rx_no_enp=0, rx_discard=0, filtered_pak=0
 tx_one_col_err=25433, tx_more_col_err=13805, tx_deferred_err=128350
 tx_underrun_err=0, , tx_loss_carrier_err=3501
 tx_exc_collision_err=0, fatal_tx_err=1, tx_recovery_count=36
 fast_throttle_count=0, fast_unthrottle_count=0, max_pause_timeout=0

 

thanks

when internet gone 8 packets lost and internet go back and i can't ping the default router when internet go down.

i found the problem it was the duplex i set it on full and now all it works good thanks all

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