You could probably create a static route from router 1 to router 4 with a priority that is better than the other options so it goes there unless the link is down.
I have 4 Cisco routers connected to our Dell Powerconnect 7024. This is  a lab environment where I am trying to have each router (2 per site) act as a WAN access point for these 2 sites.               Site 1                                                                                                                           Site 2                                                         Router 2                                         Router 3 Client PC ------Dumb_switch                         PowerConnect                            Dumb_switch------Client PC                                                         Router 1                                         Router 4   There are a few other Vlans on the switch with connected devices. With the current configuration, these two sites can communicate with any other 'site' connected to the switch over either route, except for each other.  The interfaces directly connected to the router are in trunk mode, as this is the only way I could get the dell to communicate with the Cisco. Ive read in other threads that general mode is usually suggested on the powerconnect, but did not have any luck with that setup. Router 1 -----> Gi1/0/15 (vlan 10) Router 2 ----->Gi1/0/14 (vlan 11) Router 3 ----->Gi1/0/22 (vlan 16) Router 4 ----->Gi1/0/23 (vlan 14) Example: a ping from Site 1 can reach int 22 of the switch with no problem, but I cannot ping next hop to R3. Since every other device on this switch can talk to these sites I am not clear on if the issue is my config of the dell switch or on the routers. Any input would be greatly appreciated. Thanks! !Current Configuration:!System Description "PowerConnect 7024, 5.1.2.3, VxWorks 6.6"!System Software Version 5.1.2.3!System Operational Mode "Normal"!configuregvrp enablevlan 2-7,9-14,16exitvlan 2name "BOSTON"exitvlan 3name "MIAMI"exitvlan 4name "LA"exitvlan 5name "SEATTLE"exitvlan 6name "DALLAS"exitvlan 7name "London"exitvlan 9name "Frankfurt"exitvlan 10name "Rome"exitvlan 11name "Sczecin"exitvlan 12name "Budapest"exitvlan 13name "Moscow"exitvlan 14name "Quebec"exit--More-- or (q)uitvlan 16name "Winnipeg"exithostname "Devlin"slot 1/0 2 ! PowerConnect 7024clock timezone -5 minutes 0stackmember 1 2 ! PCT7024exitinterface out-of-bandshutdownexitno ip domain-lookupip domain-name "local"ip routingip route 0.0.0.0 0.0.0.0 172.16.37.3ip route 172.16.37.160 255.255.255.240 172.16.37.162ip route 172.16.37.112 255.255.255.240 172.16.37.162ip route 172.16.37.112 255.255.255.240 172.16.37.147ip route 172.16.37.144 255.255.255.240 172.16.37.147ip route 172.16.37.240 255.255.255.240 172.16.37.244ip route 172.16.37.224 255.255.255.240 172.16.37.244ip route 172.16.37.224 255.255.255.240 172.16.37.217--More-- or (q)uitip route 172.16.37.208 255.255.255.240 172.16.37.217arp 172.16.37.162 0022.9057.7F51interface vlan 1ip address 172.16.37.4 255.255.255.240bandwidth 10000ip ospf cost 10exitinterface vlan 2ip address 172.16.37.17 255.255.255.240exitinterface vlan 3ip address 172.16.37.33 255.255.255.240exitinterface vlan 4ip address 172.16.37.49 255.255.255.240exitinterface vlan 5ip address 172.16.37.65 255.255.255.240exitinterface vlan 6ip address 172.16.37.81 255.255.255.240exitinterface vlan 7--More-- or (q)uitip address 172.16.37.97 255.255.255.240exitinterface vlan 9ip address 172.16.37.129 255.255.255.240bandwidth 10000exitinterface vlan 10ip address 172.16.37.145 255.255.255.240bandwidth 1000ip irdpexitinterface vlan 11ip address 172.16.37.161 255.255.255.240bandwidth 1000ip irdpexitinterface vlan 12ip address 172.16.37.177 255.255.255.240bandwidth 100000exitinterface vlan 13ip address 172.16.37.193 255.255.255.240bandwidth 1000exitinterface vlan 14ip address 172.16.37.209 255.255.255.240bandwidth 1000exitinterface vlan 16ip address 172.16.37.241 255.255.255.240bandwidth 1000ip ospf cost 100exitno flowcontrol!interface Gi1/0/3spanning-tree portfastexit!interface Gi1/0/4spanning-tree portfastexit!interface Gi1/0/5spanning-tree portfastswitchport access vlan 2exit!interface Gi1/0/6spanning-tree portfastswitchport access vlan 3exit!interface Gi1/0/7spanning-tree portfastswitchport access vlan 4exit!interface Gi1/0/8spanning-tree portfastswitchport access vlan 5exit!interface Gi1/0/9switchport access vlan 6exit!interface Gi1/0/10switchport access vlan 7exit!interface Gi1/0/11spanning-tree portfastswitchport mode trunkexit!interface Gi1/0/12spanning-tree portfastswitchport mode trunkexit!interface Gi1/0/13switchport access vlan 9exit!interface Gi1/0/14speed 100duplex fullswitchport mode trunkswitchport general allowed vlan add 10 taggedswitchport access vlan 10exit!interface Gi1/0/15speed 100duplex fullswitchport mode trunkswitchport general allowed vlan add 11 taggedswitchport access vlan 11exit!interface Gi1/0/16switchport access vlan 12exit!interface Gi1/0/17switchport access vlan 12exit!interface Gi1/0/18switchport access vlan 13exit!interface Gi1/0/19switchport access vlan 13exit!interface Gi1/0/22speed 100duplex fullswitchport mode trunkswitchport general allowed vlan add 16 taggedswitchport access vlan 16exit!interface Gi1/0/23speed 100duplex fullswitchport mode trunkswitchport general allowed vlan add 14switchport access vlan 14exit!interface Gi1/0/24    
Powerconnect Switch and Cisco Routers