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Minary
I am doing the labs from the cisco handbook. This is the 4th one I have done lab.
Is there the possibility of a GNS3 bug that would cause an interface to drop to up/down 30 secs after going to up/up when it is activated.
I know GNS3 ignores the clock rates but I tried taking that on and off too.
I am using the configs from the book. R1-R2 is fine. R2-R3
R3(config)#in s1/1
R3(config-if)#no sh
R3(config-if)#shut
R3(config-if)#no
*Mar 1 00:31:08.783: %LINK-5-CHANGED: Interface Serial1/1, changed state to administratively down
R3(config-if)#no shut
R3(config-if)#
*Mar 1 00:31:16.911: %LINK-3-UPDOWN: Interface Serial1/1, changed state to up
*Mar 1 00:31:17.911: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/1, changed state to up
R3(config-if)#
*Mar 1 00:31:42.327: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/1, changed state to down
c3725-adventerprisek9-mz.124-12.image
R2:
Current configuration : 1682 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R2
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
ip cef
ip tcp synwait-time 5
!
!
!
!
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
interface Loopback1
ip address 192.168.200.1 255.255.255.252
!
interface Loopback5
ip address 192.168.200.5 255.255.255.252
!
interface Loopback9
ip address 192.168.200.9 255.255.255.252
!
interface Loopback13
ip address 192.168.200.13 255.255.255.252
!
interface Loopback17
ip address 192.168.200.17 255.255.255.252
!
interface Loopback21
ip address 192.168.200.21 255.255.255.252
!
interface Loopback25
ip address 192.168.200.25 255.255.255.252
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial1/0
bandwidth 64
ip address 192.168.100.2 255.255.255.248
serial restart-delay 0
!
interface Serial1/1
bandwidth 64
ip address 10.1.1.2 255.255.255.248
serial restart-delay 0
clock rate 64000
!
interface Serial1/2
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/3
no ip address
shutdown
serial restart-delay 0
!
router eigrp 100
network 10.0.0.0
network 192.168.100.0
network 192.168.200.0
no auto-summary
!
!
!
no ip http server
no ip http secure-server
!
!
!
!
!
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
R3:
Current configuration : 1737 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R3
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
ip cef
ip tcp synwait-time 5
!
!
!
!
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
interface Loopback1
ip address 192.168.1.1 255.255.254.0
!
interface Loopback5
ip address 192.168.5.5 255.255.254.0
!
interface Loopback9
ip address 192.168.9.9 255.255.254.0
!
interface Loopback13
ip address 192.168.13.13 255.255.254.0
!
interface Loopback17
ip address 192.168.17.17 255.255.254.0
!
interface Loopback21
ip address 192.168.21.21 255.255.254.0
!
interface Loopback25
ip address 192.168.25.25 255.255.254.0
!
interface Loopback100
ip address 10.1.3.1 255.255.255.252
!
interface Loopback172
ip address 172.16.1.1 255.255.255.0
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial1/0
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/1
bandwidth 64
ip address 10.1.1.3 255.255.255.248
serial restart-delay 0
!
interface Serial1/2
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/3
no ip address
shutdown
serial restart-delay 0
!
router eigrp 100
network 10.0.0.0
network 172.16.0.0
network 192.168.0.0 0.0.31.255
no auto-summary
!
!
!
no ip http server
no ip http secure-server
!
!
!
!
!
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
thanks !
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Comments
EdTheLad
The clock rate command needs to be applied on a DCE interface, as apposed to a DTE interface. If you run the command "show controllers s1/1" you can see if the interface is dce or dte. If both are DTE you will need to have a look at the other serial interfaces on the router to find a dce. I'm not sure how GNS assigns dte/dce, on IOU its assigned on a per slot basis, i.e. slot 0,2,4.. = dte; slot 1,3,5.. = dce
Minary
Both interfaces are dce.
I tried a fresh interface with just ip address configured manually with the same result.
I saw this here:
GNS3 • View topic - FAQ and Known Issues
"
Why my serial connection works though the interfaces are both DCE?
GNS3/Dynamips doesn't emulate the physical layer which is why the serial connections work even though they are both DCE."
Dieg0M
What IOS are you using? The clock rate on my IOS gets set to 2000000 by default and works fine.
Minary
this is the image. It works fine for everything else. I thought I was possibly not understanding a configuration.
c3725-adventerprisek9-mz.124-12.image
Dieg0M
Try c3725-adventerprisek9-mz.124-15.T14. This image is known to have problems with interface buffers on multicast traffic.
Minary
I changed the image and started the lab from scratch and it worked perfectly.
thanks
Minary
I got the same problem again setting up a different lab but with serial interface, all other serials on the other routers were fine.
I fixed it by loading another slot of serial interfaces.
How often do people have buggy issues with GNS3 ?
networker050184
Never had that issue before. The only time I've had issues with things dropping out is when my CPU gets taxed. Have you set your idlepc values correctly to rule that out?
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