Hi folks. If you see this topic then you have some problem to mirgation centos 8 to centos 8 stream.
STEP 1: Go to /etc/yum.repos.d/
STEP 2: Change /etc/yum/repos.d/Centos-Appstream 2 directives. You need comment
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=BaseOS&infra=$infra #baseurl=http://mirror.centos.org/$contentdir/$releasever/BaseOS/$basearch/os/
And add this record
baseurl=http://mirror.yandex.ru/centos/8-stream/AppStream/x86_64/os/?contentdir/$releasever/BaseOS/$basearch/os/
Change /etc/yum/repos.d/Centos-BaseOS too.
STEP 3: dnf install centos-release-stream
STEP 4: dnf swap centos-{linux,stream}-repos
STEP 5: dnf distro-sync
STEP 6: dnf update -y
STEP 7: reboot