http://download.opensuse.org/repositories/home:/kamailio:/v5.1.x-rpms/CentOS_7/x86_64/kamailio-5.1.4-1.el7.centos.x86_64.rpm.mirrorlist

In file information block you can see file size is 5643596 bytes. But if you download it - file size is 5642888. And it is not possible to install kamailio 5.1.4 on centos7 from repo.

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