r4 has 2 equal cost paths as depicted in the topo...
R4(config)#do sh ip eigrp topo 1.1.1.0/24
EIGRP-IPv4 Topology Entry for AS(1)/ID(4.4.4.4) for 1.1.1.0/24
State is Passive, Query origin flag is 1, 2 Successor(s), FD is 2560002560
Descriptor Blocks:
172.16.1.3 (FastEthernet1/1), from 172.16.1.3, Send flag is 0x0
Composite metric is (2560002560/2560000000), route is External
Vector metric:
Minimum bandwidth is 1 Kbit
Total delay is 100 microseconds
Reliability is 1/255
Load is 255/255
Minimum MTU is 1500
Hop count is 1
Originating router is 3.3.3.3
External data:
AS number of route is 1
External protocol is OSPF, external metric is 3
Administrator tag is 0 (0x00000000)
172.16.2.3 (FastEthernet0/0), from 172.16.2.3, Send flag is 0x0
Composite metric is (2560002560/2560000000), route is External
Vector metric:
Minimum bandwidth is 1 Kbit
Total delay is 100 microseconds
Reliability is 1/255
Load is 255/255
Minimum MTU is 1500
Hop count is 1
Originating router is 3.3.3.3
External data:
AS number of route is 1
External protocol is OSPF, external metric is 3
Administrator tag is 0 (0x00000000)
with cef enabled one path will be chosen, and there will be no load balancing...
R4(config)#do sh ip route 1.1.1.1
Routing entry for 1.1.1.0/24
Known via "eigrp 1", distance 170, metric 2560002560, type external
Redistributing via eigrp 1
Last update from 172.16.1.3 on FastEthernet1/1, 00:24:22 ago
Routing Descriptor Blocks:
* 172.16.2.3, from 172.16.2.3, 00:24:22 ago, via FastEthernet0/0
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
172.16.1.3, from 172.16.1.3, 00:24:22 ago, via FastEthernet1/1
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
note the asterisk... the asterisk should bounce between the routes, either per packet or per destination, depending on your determination...
R4(config)#do ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 52/58/68 ms
R4(config)#do sh ip route 1.1.1.1
Routing entry for 1.1.1.0/24
Known via "eigrp 1", distance 170, metric 2560002560, type external
Redistributing via eigrp 1
Last update from 172.16.1.3 on FastEthernet1/1, 00:26:03 ago
Routing Descriptor Blocks:
* 172.16.2.3, from 172.16.2.3, 00:26:03 ago, via FastEthernet0/0
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
172.16.1.3, from 172.16.1.3, 00:26:03 ago, via FastEthernet1/1
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
R4(config)#do ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 56/59/68 ms
R4(config)#do sh ip route 1.1.1.1
Routing entry for 1.1.1.0/24
Known via "eigrp 1", distance 170, metric 2560002560, type external
Redistributing via eigrp 1
Last update from 172.16.1.3 on FastEthernet1/1, 00:26:11 ago
Routing Descriptor Blocks:
* 172.16.2.3, from 172.16.2.3, 00:26:11 ago, via FastEthernet0/0
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
172.16.1.3, from 172.16.1.3, 00:26:11 ago, via FastEthernet1/1
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
the damn asterisk doesn't float...
turn cef off and now your asterisk is buoyant...
R4(config)#no ip cef
R4(config)#do sh ip route 1.1.1.1
Routing entry for 1.1.1.0/24
Known via "eigrp 1", distance 170, metric 2560002560, type external
Redistributing via eigrp 1
Last update from 172.16.1.3 on FastEthernet1/1, 00:27:05 ago
Routing Descriptor Blocks:
* 172.16.2.3, from 172.16.2.3, 00:27:05 ago, via FastEthernet0/0
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
172.16.1.3, from 172.16.1.3, 00:27:05 ago, via FastEthernet1/1
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
R4(config)#do ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 52/60/68 ms
R4(config)#do sh ip route 1.1.1.1
Routing entry for 1.1.1.0/24
Known via "eigrp 1", distance 170, metric 2560002560, type external
Redistributing via eigrp 1
Last update from 172.16.1.3 on FastEthernet1/1, 00:27:19 ago
Routing Descriptor Blocks:
172.16.2.3, from 172.16.2.3, 00:27:19 ago, via FastEthernet0/0
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
* 172.16.1.3, from 172.16.1.3, 00:27:19 ago, via FastEthernet1/1
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
R4(config)#do ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 40/63/88 ms
R4(config)#do sh ip route 1.1.1.1
Routing entry for 1.1.1.0/24
Known via "eigrp 1", distance 170, metric 2560002560, type external
Redistributing via eigrp 1
Last update from 172.16.1.3 on FastEthernet1/1, 00:27:33 ago
Routing Descriptor Blocks:
* 172.16.2.3, from 172.16.2.3, 00:27:33 ago, via FastEthernet0/0
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
172.16.1.3, from 172.16.1.3, 00:27:33 ago, via FastEthernet1/1
Route metric is 2560002560, traffic share count is 1
Total delay is 100 microseconds, minimum bandwidth is 1 Kbit
Reliability 1/255, minimum MTU 1500 bytes
Loading 255/255, Hops 1
R4(config)#
but you can turn on ip load sharing for cef...
R4(config-if)#do sh cef int f0/0
FastEthernet0/0 is up (if_number 2)
Corresponding hwidb fast_if_number 2
Corresponding hwidb firstsw->if_number 2
Internet address is 172.16.2.4/24
ICMP redirects are always sent
Per packet load-sharing is disabled
IP unicast RPF check is disabled
IP policy routing is disabled
BGP based policy accounting on input is disabled
BGP based policy accounting on output is disabled
Hardware idb is FastEthernet0/0
Fast switching type 1, interface type 18
IP CEF switching enabled
IP CEF switching turbo vector
IP CEF turbo switching turbo vector
IP prefix lookup IPv4 mtrie 8-8-8-8 optimized
Input fast flags 0x0, Output fast flags 0x0
ifindex 2(2)
Slot Slot unit 0 VC -1
IP MTU 1500
R4(config-if)#ip load-shar ?
per-destination Deterministic distribution
per-packet Random distribution
refs:
http://www.cisco.com/en/US/tech/tk827/tk831/technologies_tech_note09186a0080094806.shtml
http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094820.shtml
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