In order to conserve the limited bandwidth available, ISO images are not downloadable from mirror.centos.org
The following mirrors should have the ISO images available:
http://mirror.web-ster.com/centos/8.3.2011/isos/x86_64/
http://repos.eggycrew.com/centos/8.3.2011/isos/x86_64/
http://mirror.wdc1.us.leaseweb.net/centos/8.3.2011/isos/x86_64/
http://centos-distro.cavecreek.net/centos/8.3.2011/isos/x86_64/
http://mirror.es.its.nyu.edu/centos/8.3.2011/isos/x86_64/
http://mirrors.cmich.edu/centos/8.3.2011/isos/x86_64/
http://bay.uchicago.edu/centos/8.3.2011/isos/x86_64/
http://mirrors.sonic.net/centos/8.3.2011/isos/x86_64/
http://mirror.mobap.edu/centos/8.3.2011/isos/x86_64/
http://ftpmirror.your.org/pub/centos/8.3.2011/isos/x86_64/
http://linux.mirrors.es.net/centos/8.3.2011/isos/x86_64/
http://mirrors.vcea.wsu.edu/centos/8.3.2011/isos/x86_64/
http://repos.hou.layerhost.com/centos/8.3.2011/isos/x86_64/
http://mirror.cs.vt.edu/pub/CentOS/8.3.2011/isos/x86_64/
http://mirrors.rit.edu/centos/8.3.2011/isos/x86_64/
http://mirror.nodespace.net/centos/8.3.2011/isos/x86_64/
http://mirrors.unifiedlayer.com/centos/8.3.2011/isos/x86_64/
http://repos.dfw.quadranet.com/centos/8.3.2011/isos/x86_64/
http://centos.den.host-engine.com/8.3.2011/isos/x86_64/
http://mirror.sjc02.svwh.net/centos/8.3.2011/isos/x86_64/
http://mirror.vtti.vt.edu/centos/8.3.2011/isos/x86_64/
http://repos.forethought.net/centos/8.3.2011/isos/x86_64/
http://mirror.vacares.com/centos/8.3.2011/isos/x86_64/
http://centos.mirror.shastacoe.net/centos/8.3.2011/isos/x86_64/
http://mirrors.tripadvisor.com/centos/8.3.2011/isos/x86_64/
http://mirror.centos.lax1.serverforge.org/8.3.2011/isos/x86_64/
http://mirror.teklinks.com/centos/8.3.2011/isos/x86_64/
http://mirrors.oit.uci.edu/centos/8.3.2011/isos/x86_64/
http://packages.oit.ncsu.edu/centos/8.3.2011/isos/x86_64/
http://sjc.edge.kernel.org/centos/8.3.2011/isos/x86_64/
+ others, see the full list of mirrors: https://www.centos.org/download/mirrors/
Mirrors verified Thu Jun 3 09:10:46 2021 UTC
You can also download the ISO images using bittorrent, a peer-to-peer file sharing protocol. The .torrent files can be found from CentOS mirrors. Various bittorrent clients are available, including (in no particular order of preference): utorrent, vuze (Azureus), BitTorrent, Deluge, ctorrent, ktorrent, rtorrent and transmission. Packaged copies of various torrent clients for CentOS can be found in the repositories listed in the following wiki article: https://wiki.centos.org/AdditionalResources/Repositories
The following mirrors should have the ISO images available:
http://mirror.web-ster.com/centos/8.3.2011/isos/x86_64/
http://repos.eggycrew.com/centos/8.3.2011/isos/x86_64/
http://mirror.wdc1.us.leaseweb.net/centos/8.3.2011/isos/x86_64/
http://centos-distro.cavecreek.net/centos/8.3.2011/isos/x86_64/
http://mirror.es.its.nyu.edu/centos/8.3.2011/isos/x86_64/
http://mirrors.cmich.edu/centos/8.3.2011/isos/x86_64/
http://bay.uchicago.edu/centos/8.3.2011/isos/x86_64/
http://mirrors.sonic.net/centos/8.3.2011/isos/x86_64/
http://mirror.mobap.edu/centos/8.3.2011/isos/x86_64/
http://ftpmirror.your.org/pub/centos/8.3.2011/isos/x86_64/
http://linux.mirrors.es.net/centos/8.3.2011/isos/x86_64/
http://mirrors.vcea.wsu.edu/centos/8.3.2011/isos/x86_64/
http://repos.hou.layerhost.com/centos/8.3.2011/isos/x86_64/
http://mirror.cs.vt.edu/pub/CentOS/8.3.2011/isos/x86_64/
http://mirrors.rit.edu/centos/8.3.2011/isos/x86_64/
http://mirror.nodespace.net/centos/8.3.2011/isos/x86_64/
http://mirrors.unifiedlayer.com/centos/8.3.2011/isos/x86_64/
http://repos.dfw.quadranet.com/centos/8.3.2011/isos/x86_64/
http://centos.den.host-engine.com/8.3.2011/isos/x86_64/
http://mirror.sjc02.svwh.net/centos/8.3.2011/isos/x86_64/
http://mirror.vtti.vt.edu/centos/8.3.2011/isos/x86_64/
http://repos.forethought.net/centos/8.3.2011/isos/x86_64/
http://mirror.vacares.com/centos/8.3.2011/isos/x86_64/
http://centos.mirror.shastacoe.net/centos/8.3.2011/isos/x86_64/
http://mirrors.tripadvisor.com/centos/8.3.2011/isos/x86_64/
http://mirror.centos.lax1.serverforge.org/8.3.2011/isos/x86_64/
http://mirror.teklinks.com/centos/8.3.2011/isos/x86_64/
http://mirrors.oit.uci.edu/centos/8.3.2011/isos/x86_64/
http://packages.oit.ncsu.edu/centos/8.3.2011/isos/x86_64/
http://sjc.edge.kernel.org/centos/8.3.2011/isos/x86_64/
+ others, see the full list of mirrors: https://www.centos.org/download/mirrors/
Mirrors verified Thu Jun 3 09:10:46 2021 UTC
You can also download the ISO images using bittorrent, a peer-to-peer file sharing protocol. The .torrent files can be found from CentOS mirrors. Various bittorrent clients are available, including (in no particular order of preference): utorrent, vuze (Azureus), BitTorrent, Deluge, ctorrent, ktorrent, rtorrent and transmission. Packaged copies of various torrent clients for CentOS can be found in the repositories listed in the following wiki article: https://wiki.centos.org/AdditionalResources/Repositories