c836 router rfc1483-bridged with NAT / problem every five minutes

We have a Cisco 836 ADSL over ISDN router, configured for RFC1483 bridging, with NAT. It seems to be working fine, however, every five minutes (exact) it brings down the ATM0 interface, which brings down the bridge (BVI1). After about 20 seconds it comes up again, and connection comes back up, no errors logged other than that the connection was brought down.

Has anyone encountered a similiar problem? Any hints for troubleshooting?

Thanks in advance.

Pjn

Reply to
pigeaud
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  1. post sh version and running config

  1. enable logging buffer

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

  1. after interface goes down do a show log to see if there are any relevant messages. if so post here
Reply to
Merv

Here we go: Merv wrote:

sh version: Cisco IOS Software, C836 Software (C836-K9O3Y6-M), Version 12.3(8)T11, RELEASE SOFTWARE (fc1)

ROM: System Bootstrap, Version 12.2(11r)YV3, RELEASE SOFTWARE (fc2)

System image file is "flash:c836-k9o3y6-mz.123-8.T11.bin"

running config: Current configuration : 1870 bytes ! version 12.3 no service pad service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname c836 ! boot-start-marker boot-end-marker ! logging buffered 10000 debugging no logging console ! no aaa new-model ip subnet-zero ! ! ip ips po max-events 100 no ftp-server write-enable ! ! username admin privilege 15 secret 5 ! ! ! bridge irb ! ! interface Ethernet0 description $ETH-LAN$$ETH-SW-LAUNCH$$INTF-INFO-Ethernet 10/100$ ip address 192.168.20.1 255.255.255.0 ip nat inside ip virtual-reassembly hold-queue 100 out ! interface BRI0 no ip address shutdown ! interface ATM0 no ip address no ip mroute-cache atm vc-per-vp 64 no atm ilmi-keepalive dsl operating-mode auto bridge-group 1 pvc 0/34 encapsulation aal5snap ! ! interface FastEthernet1 no ip address duplex auto speed auto ! interface FastEthernet2 no ip address duplex auto speed auto ! interface FastEthernet3 no ip address duplex auto speed auto ! interface FastEthernet4 no ip address duplex auto speed auto ! interface BVI1 ip address dhcp ip nat outside ip virtual-reassembly ! ip classless ip route 0.0.0.0 0.0.0.0 BVI1 ip http server ip http authentication local ip http secure-server ip http timeout-policy idle 5 life 86400 requests 10000 ip nat inside source list 1 interface BVI1 overload ! ! access-list 1 permit 192.0.0.0 0.255.255.255 ! control-plane ! bridge 1 protocol ieee bridge 1 route ip ! line con 0 login local no modem enable line aux 0 line vty 0 4 privilege level 15 login local transport input telnet ssh ! scheduler max-task-time 5000 ! sntp server 193.67.79.202 end

already done (see config).

Jun 28 09:19:52.477: %LINK-3-UPDOWN: Interface ATM0, changed state to down Jun 28 09:19:53.477: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM0, changed state to down Jun 28 09:19:54.477: %LINK-3-UPDOWN: Interface BVI1, changed state to down Jun 28 09:19:55.477: %LINEPROTO-5-UPDOWN: Line protocol on Interface BVI1, changed state to down Jun 28 09:20:09.929: %LINK-3-UPDOWN: Interface ATM0, changed state to up Jun 28 09:20:10.929: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM0, changed state to up Jun 28 09:20:11.793: %LINK-3-UPDOWN: Interface BVI1, changed state to up Jun 28 09:20:12.793: %LINEPROTO-5-UPDOWN: Line protocol on Interface BVI1, changed state to up Jun 28 09:24:52.513: %LINK-3-UPDOWN: Interface ATM0, changed state to down Jun 28 09:24:53.513: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM0, changed state to down Jun 28 09:24:54.513: %LINK-3-UPDOWN: Interface BVI1, changed state to down Jun 28 09:24:55.513: %LINEPROTO-5-UPDOWN: Line protocol on Interface BVI1, changed state to down Jun 28 09:25:09.973: %LINK-3-UPDOWN: Interface ATM0, changed state to up Jun 28 09:25:10.973: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM0, changed state to up Jun 28 09:25:11.785: %LINK-3-UPDOWN: Interface BVI1, changed state to up Jun 28 09:25:12.785: %LINEPROTO-5-UPDOWN: Line protocol on Interface BVI1, changed state to up

As you can see, it just goes down, every five minutes.

Thanks,

Pjn

Reply to
pigeaud

Oh and, by the way, I saw a lot (392) of interface resets for ATM0, none for the other (BVI1, ETH0) interfaces. 199 Packet drops...

thanks,

Pjn

Reply to
pjn

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