debian stretch的source有问题

apt-get install -y cron pdftk ---> Running in 0f21c7fb46e8 Ign:1 http://mirrors.aliyun.com/debian stretch InRelease Get:2 http://mirrors.aliyun.com/debian-security stretch/updates InRelease [53.0 kB] Get:3 http://mirrors.aliyun.com/debian stretch-updates InRelease [93.6 kB] Get:4 http://mirrors.aliyun.com/debian stretch-backports InRelease [91.8 kB] Get:5 http://mirrors.aliyun.com/debian stretch Release [118 kB] Get:6 http://mirrors.aliyun.com/debian stretch Release.gpg [2410 B] Ign:7 http://mirrors.aliyun.com/debian-security stretch/updates/main Sources Ign:8 http://mirrors.aliyun.com/debian-security stretch/updates/main amd64 Packages Get:7 http://mirrors.aliyun.com/debian-security stretch/updates/main Sources [309 kB] Err:7 http://mirrors.aliyun.com/debian-security stretch/updates/main Sources Writing more data than expected (308784 > 308768) Hashes of expected file: - Filesize:308768 [weak] - SHA256:5e637caa14288e2048f14ad74ac54cdafa6fbf74ffe88c7dbb92cc5a4fae0d57 - SHA1:510eaa2e48e77e31070fe4feee5c13787de2ef78 [weak] - MD5Sum:ea39c3a11b08ad9076042e7145a5e537 [weak] Release file created at: Mon, 23 Nov 2020 11:21:25 +0000 Get:8 http://mirrors.aliyun.com/debian-security stretch/updates/main amd64 Packages [627 kB] Err:8 http://mirrors.aliyun.com/debian-security stretch/updates/main amd64 Packages

Get:9 http://mirrors.aliyun.com/debian stretch-updates/main Sources [1456 B] Get:10 http://mirrors.aliyun.com/debian stretch-updates/non-free Sources [816 B] Get:11 http://mirrors.aliyun.com/debian stretch-updates/main amd64 Packages [2596 B] Get:12 http://mirrors.aliyun.com/debian stretch-updates/non-free amd64 Packages [632 B] Get:13 http://mirrors.aliyun.com/debian stretch-backports/non-free Sources [8412 B] Get:14 http://mirrors.aliyun.com/debian stretch-backports/main Sources [557 kB] Get:15 http://mirrors.aliyun.com/debian stretch-backports/contrib Sources [6528 B] Get:16 http://mirrors.aliyun.com/debian stretch-backports/main amd64 Packages [612 kB] Get:17 http://mirrors.aliyun.com/debian stretch-backports/contrib amd64 Packages [10.9 kB] Get:18 http://mirrors.aliyun.com/debian stretch-backports/non-free amd64 Packages [33.2 kB] Get:19 http://mirrors.aliyun.com/debian stretch/main Sources [6736 kB] Get:20 http://mirrors.aliyun.com/debian stretch/contrib Sources [44.5 kB] Get:21 http://mirrors.aliyun.com/debian stretch/non-free Sources [79.1 kB] Get:22 http://mirrors.aliyun.com/debian stretch/non-free amd64 Packages [78.3 kB] Get:23 http://mirrors.aliyun.com/debian stretch/main amd64 Packages [7080 kB] Get:24 http://mirrors.aliyun.com/debian stretch/contrib amd64 Packages [50.7 kB] Fetched 16.3 MB in 6s (2695 kB/s) Reading package lists... E: Failed to fetch http://mirrors.aliyun.com/debian-security/dists/stretch/updates/main/source/Sources.xz Writing more data than expected (308784 > 308768) Hashes of expected file: - Filesize:308768 [weak] - SHA256:5e637caa14288e2048f14ad74ac54cdafa6fbf74ffe88c7dbb92cc5a4fae0d57 - SHA1:510eaa2e48e77e31070fe4feee5c13787de2ef78 [weak] - MD5Sum:ea39c3a11b08ad9076042e7145a5e537 [weak] Release file created at: Mon, 23 Nov 2020 11:21:25 +0000 E: Failed to fetch http://mirrors.aliyun.com/debian-security/dists/stretch/updates/main/binary-amd64/Packages.xz
E: Some index files failed to download. They have been ignored, or old ones used instead.