Recently, I have created Linux Core 9.0 x86-64 VMware Disk (VMDK) and installed FRRrouting suite 5.0.1 on the top of it in order to test current EIGRP support in Linux (RFC 7868).
The last time I tested EIGRP with FRR 3.1-dev installed on Linux Core, FRR suffered from many bugs. In fact, they were so serious so EIGRP was not ready for use. Unfortunately, they are also presented in FRR version 5.0.1. Therefore, I advise you to use another IGP routing daemons such as OSPF or IS-IS available in FRR until the issues are resolved.
Anyway, you can use my Core Linux VMDK disk with installed FRRouting 5.0.1 to practice routing in Linux. Thanks to using minimalistic Core Linux distribution, the size of image is only about 86 MB. The Core kernel is compiled with enabled option MULTIPATH so you can test equal cost multipath routing with OSPF. The image is available in Linux Core Router/Switch appliances.