issue with Phone registration

[arysyvility60272]

Hello, sorry for my english from google translate i need help with one problem in packet tracer, im a student

IP phone from the 1st network constantly falls and goes off? a minute later, registration starts again and everything works, as soon as you call another IP, the phone drops again. I did not find the problem, who can tell?. I thought about loops in the network, but there are no loops, everything is divided by Vlan 10 data and 20 voice. The only thing I tried to turn off the third router in the network, and everything works fine, but it is not clear how it interferes with it. What methods can be used to find the problem on the network? 

topologythe problem

router 1 config

Spoiler

hostname R2
ip dhcp excluded-address 10.0.0.1 10.0.0.10
ip dhcp excluded-address 10.0.1.1 10.0.1.10
ip dhcp pool VOIP_DHCP
 network 10.0.1.0 255.255.255.0
 default-router 10.0.1.1
 option 150 ip 10.1.1.1
 dns-server 10.0.1.1
ip dhcp pool COMP_DHCP
 network 10.0.0.0 255.255.255.0
 default-router 10.0.0.1
 dns-server 10.0.0.1
interface GigabitEthernet0/0
 ip address 192.168.0.2 255.255.255.0
interface GigabitEthernet0/1
 no ip address
interface GigabitEthernet0/1.10
 description Comp
 encapsulation dot1Q 10
 ip address 10.0.0.1 255.255.255.0
interface GigabitEthernet0/1.20
 description VOIP
 encapsulation dot1Q 20
 ip address 10.0.1.1 255.255.255.0
ip route 0.0.0.0 0.0.0.0 192.168.0.1 
!

router 2 config

Spoiler

hostname R1
ip dhcp excluded-address 10.1.0.1 10.1.0.10
ip dhcp excluded-address 10.1.1.1 10.1.1.10
ip dhcp pool VOIP_DHCP
 network 10.1.1.0 255.255.255.0
 default-router 10.1.1.1
 option 150 ip 10.1.1.1
 dns-server 10.1.0.1
ip dhcp pool COMP_DHCP
 network 10.1.0.0 255.255.255.0
 default-router 10.1.0.1
 dns-server 10.1.0.1
spanning-tree mode pvst
interface FastEthernet0/0
 ip address 192.168.0.1 255.255.255.0
interface FastEthernet0/1
 no ip address
interface FastEthernet0/1.10
 description Comp
 encapsulation dot1Q 10
 ip address 10.1.0.1 255.255.255.0
interface FastEthernet0/1.20
 description VOIP
 encapsulation dot1Q 20
 ip address 10.1.1.1 255.255.255.0
interface FastEthernet1/0
 ip address 192.168.20.1 255.255.255.0
interface FastEthernet1/1
 no ip address
router rip
ip route 0.0.0.0 0.0.0.0 192.168.0.2 
ip route 0.0.0.0 0.0.0.0 192.168.20.2 
telephony-service
 max-ephones 24
 max-dn 48
 ip source-address 10.1.1.1 port 2000
ephone-dn 1
 number 101500
ephone-dn 2
 number 101502
ephone 1
 device-security-mode none
 mac-address 00D0.D3D1.BC2D
 type 7960
 button 1:1
ephone 2
 device-security-mode none
 mac-address 0060.4724.C75A
 type 7960
 button 1:2
end

router 3 config

Spoiler

hostname Router

ip dhcp excluded-address 10.2.0.1 10.2.0.10
ip dhcp pool COMP_DHCP
 network 10.2.0.0 255.255.255.0
 default-router 10.2.0.1
 dns-server 10.2.0.1

interface GigabitEthernet0/0
 ip address 192.168.20.2 255.255.255.0

interface GigabitEthernet0/1
 ip address 10.2.0.1 255.255.255.0

Also atached  .pkt file from packet tracer

[Scott Leport · Accepted solution]

Hi there,

I think the Cisco Learning Network is more appropriate for this sort of question. In any case, the first thing that sticks out to me is that you have 2 default routes configured on R1 (Router 2 config in your post) and that is going to load balance the traffic so you will find that 50% of the time the traffic takes the desired path and 50% of the time the traffic doesn't take the desired path. At a high-level I would suggest fixing that and configuring an IGP across your three routers and your connectivity issues might get sorted. 

[arysyvility60272]

Thank you very much kind person, I wrote static routing correctly and the problem was fixed. The problem was incorrect routing. Wish you all the best!