Armadilloフォーラム

apt-getで、パッケージをダウンロードしようとすると、
以下のエラーに遭遇します。
リポジトリの参照先の変更等が必要でしょうか？

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[デフォルトのリポジトリ設定]

root@armadillo:~# vi /etc/apt/sources.list

deb http://ftp.jp.debian.org/debian/ jessie main non-free contrib
deb-src http://ftp.jp.debian.org/debian/ jessie main non-free contrib

deb http://security.debian.org/ jessie/updates main non-free contrib
deb-src http://security.debian.org/ jessie/updates main non-free contrib

deb http://download.atmark-techno.com/debian/ jessie main contrib non-free

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[APT-GET時のログ]
root@armadillo:~# apt-get install ssh
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
libwrap0 ncurses-term openssh-server openssh-sftp-server tcpd
Suggested packages:
ssh-askpass rssh molly-guard ufw monkeysphere
The following NEW packages will be installed:
libwrap0 ncurses-term openssh-server openssh-sftp-server ssh tcpd
0 upgraded, 6 newly installed, 0 to remove and 2 not upgraded.
Need to get 358 kB/1008 kB of archives.
After this operation, 3294 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Err http://ftp.jp.debian.org/debian/ jessie/main openssh-sftp-server armhf 1:6.7p1-5+deb8u3
404 Not Found
Err http://security.debian.org/ jessie/updates/main openssh-sftp-server armhf 1:6.7p1-5+deb8u3
404 Not Found [IP: 151.101.88.204 80]
Err http://security.debian.org/ jessie/updates/main openssh-server armhf 1:6.7p1-5+deb8u3
404 Not Found [IP: 151.101.88.204 80]
E: Failed to fetch http://security.debian.org/pool/updates/main/o/openssh/openssh-sftp-ser… 404 Not Found [IP: 151.101.88.204 80]

E: Failed to fetch http://security.debian.org/pool/updates/main/o/openssh/openssh-server_6… 404 Not Found [IP: 151.101.88.204 80]

E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?