This is the output from my RedHat 8.0 after running ifconfig. The MULTICAST value appears in mine as well. Keep in mind that I am behind a router, and use NAT, but all of the other setting should be relevant.
eth0 Link encap:Ethernet HWaddr 00
0:09:ED:61:61
inet addr:192.168.0.100 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:529 errors:0 dropped:0 overruns:0 frame:0
TX packets:511 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:315141 (307.7 Kb) TX bytes:47976 (46.8 Kb)
Interrupt:10 Base address:0xdc00
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:12 errors:0 dropped:0 overruns:0 frame:0
TX packets:12 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:800 (800.0 b) TX bytes:800 (800.0 b)
Don't know if this helps, but you can at least use it as another example of a working eth0
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