conda 安装宏基因组软件megahit出现CondaHTTPError: HTTP 000 CONNECTION FAILED for url问题

使用conda 安装MEGAHIT 软件时，出现 Solving environment: failed CondaHTTPError: HTTP 000 CONNECTION FAILED for url <https://repo.anaconda.com/pkgs/r/linux-64/repodata.json.bz2>：的错误：

直接安装

$ ./conda install -c bioconda megahit
Solving environment: failed

CondaHTTPError: HTTP 000 CONNECTION FAILED for url <https://repo.anaconda.com/pkgs/r/linux-64/repodata.json.bz2>
Elapsed: -

An HTTP error occurred when trying to retrieve this URL.
HTTP errors are often intermittent, and a simple retry will get you on your way.

.....

报错，显示没有源。

配置最新的清华源。这注意必须是最新的，有些旧的不能使用，可以点击链接去看看最新的源是什么？

# vi ~/.condarc 

把下列内容拷进去，保存.condarc文件

channels:
  - https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main
  - https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/r
  - https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/msys2
custom_channels:
  conda-forge: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
  msys2: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
  bioconda: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
  menpo: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
  pytorch: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
  simpleitk: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud

再次运行

# ./conda install -c bioconda megahit
Solving environment: done

## Package Plan ##

  environment location: /home/SLX/miniconda3

  added / updated specs: 
    - megahit


The following packages will be downloaded:

    package                    |            build
    ---------------------------|-----------------
    openjdk-8.0.152            |       h7b6447c_3       128.5 MB  https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main
    _libgcc_mutex-0.1          |             main           3 KB  https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main
    libgcc-ng-9.1.0            |       hdf63c60_0         8.1 MB  https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main
    ca-certificates-2021.1.19  |       h06a4308_1         125 KB  https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main
    wheel-0.36.2               |     pyhd3eb1b0_0          31 KB  https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main
    certifi-2020.12.5          |   py36h06a4308_0         144 KB  https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main
    tk-8.6.10                  |       hbc83
    
    ........

安装成功

运行megahit

$ megahit -h # 查看参数
$ megahit -1 KAPA-NDV-9_FKDL210032958-1a_1.clean.fq.gz -2 KAPA-NDV-9_FKDL210032958-1a_2.clean.fq.gz -o megahit_contig_9/ --min-contig-len 2000 # 输出2000bp以上的contig