引言
ceph 也提供s3 对象存储功能，有时候开发s3相关的代码，需要测试。访问s3 对象，有一些开源的工具，比如cloudberry和s3 browser。 RD出身，多年Linux平台开发，不太喜欢用鼠标点点点来测试，还是比较喜欢命令行，觉得效率要高一些。
如果通过命令行来操作ceph提供的s3 功能呢？不多说，本文介绍s3cmd
配置
创建个bean_li账户，ceph会生成access_key 和 secret key来访问s3功能。
root@node2:~# radosgw-admin user info --uid bean_li
{ "user_id": "bean_li",
"display_name": "bean_li",
"email": "bean@163.com",
"suspended": 0,
"max_buckets": 1000,
"auid": 0,
"subusers": [
{ "id": "bean_li:bean_li",
"permissions": "full-control"}],
"keys": [
{ "user": "bean_li",
"access_key": "53GRNIWPBPD86SENNC4T",
"secret_key": "nV4tsr7MXTpnZeFx9eWffNL9ptcsYC7tbp6nMxXn"}],
"swift_keys": [
{ "user": "bean_li",
"secret_key": "1"},
{ "user": "bean_li:bean_li",
"secret_key": "1"}],
"caps": [],
"op_mask": "read, write, delete",
"default_placement": "",
"placement_tags": [],
"bucket_quota": { "enabled": false,
"max_size_kb": -1,
"max_objects": -1},
"user_quota": { "enabled": false,
"max_size_kb": -1,
"max_objects": -1},
"temp_url_keys": []}
有了这两个key，我们就可配置s3cmd的配置文件了：
root@node:~# s3cmd --configure
Enter new values or accept defaults in brackets with Enter.
Refer to user manual for detailed description of all options.
Access key and Secret key are your identifiers for Amazon S3. Leave them empty for using the env variables.
Access Key: 1CY0KPDKZ2IKBEV1VOY0
Secret Key: YxXqS15wzNMwB1trlZHa6XdIb17YeC4RQtnq7OYu
Default Region [US]:
Use "s3.amazonaws.com" for S3 Endpoint and not modify it to the target Amazon S3.
S3 Endpoint [s3.amazonaws.com]: 172.17.72.227
Use "%(bucket)s.s3.amazonaws.com" to the target Amazon S3. "%(bucket)s" and "%(location)s" vars can be used
if the target S3 system supports dns based buckets.
DNS-style bucket+hostname:port template for accessing a bucket [%(bucket)s.s3.amazonaws.com]: n
Encryption password is used to protect your files from reading
by unauthorized persons while in transfer to S3
Encryption password:
Path to GPG program [/usr/bin/gpg]:
When using secure HTTPS protocol all communication with Amazon S3
servers is protected from 3rd party eavesdropping. This method is
slower than plain HTTP, and can only be proxied with Python 2.7 or newer
Use HTTPS protocol [Yes]: n
On some networks all internet access must go through a HTTP proxy.
Try setting it here if you can't connect to S3 directly
HTTP Proxy server name:
New settings:
Access Key: 1CY0KPDKZ2IKBEV1VOY0
Secret Key: YxXqS15wzNMwB1trlZHa6XdIb17YeC4RQtnq7OYu
Default Region: US
S3 Endpoint: 172.17.72.227
DNS-style bucket+hostname:port template for accessing a bucket: n
Encryption password:
Path to GPG program: /usr/bin/gpg
Use HTTPS protocol: False
HTTP Proxy server name:
HTTP Proxy server port: 0
Test access with supplied credentials? [Y/n] n
Save settings? [y/N] y
Configuration saved to '/root/.s3cfg'
root@node:~#
root@node:~#
root@node:~# s3cmd ls
2022-11-04 01:57 s3://local_227
root@node:~#
root@node:~#
从上面可以看出，会生成用户的配置文件/root/.s3cfg,但是标准的s3是amazon提供的，因此：
host_base = s3.amazonaws.com
host_bucket = %(bucket)s.s3.amazonaws.com
显然，如果不修改配置文件，就会访问官方正式的amazon s3 服务，而ceph提供的是兼容服务，比如让web service请求发送到ceph集群中的某个主机，或者ceph 集群提供的域名。
因此将上面两行中的s3.amazonaws.com改成集群中的IP或者集群提供的域名。
host_base = 10.16.17.99
host_bucket = %(bucket)s.10.16.17.99
配置至此完毕，可以用s3cmd来访问ceph提供的功能了
使用
毫无疑问，配置之后，并问创建任何bucket，因此s3cmd ls返回时空的。
root@node2:~# s3cmd ls
root@node2:~#
创建bucket：
root@node2:~# s3cmd mb s3://bean_bucket
Bucket 's3://bean_bucket/' created
root@node2:~# s3cmd ls
2016-03-30 15:22 s3://bean_bucke
上传文件到bucket
root@node2:~# s3cmd put /var/log/kern.log s3://bean_bucket/log/
/var/log/kern.log -> s3://bean_bucket/log/kern.log [1 of 1]
281171 of 281171 100% in 0s 1941.34 kB/s done
root@node2:~# s3cmd ls
2016-03-30 15:22 s3://bean_bucket
root@node2:~# s3cmd ls s3://bean_bucket/log/
2016-03-30 15:25 281171 s3://bean_bucket/log/kern.log
删除bucket中的对象
root@node2:~# s3cmd del s3://bean_bucket/log/kern.log
File s3://bean_bucket/log/kern.log deleted
root@node2:~# s3cmd ls s3://bean_bucket/log/
root@node2:~# s3cmd ls s3://bean_bucket
下载bucket中的对象到本地
root@node2:~# s3cmd put /var/log/syslog s3://bean_bucket/
/var/log/syslog -> s3://bean_bucket/syslog [1 of 1]
302838 of 302838 100% in 0s 1138.84 kB/s done
root@node2:~#
root@node2:~# s3cmd get s3://bean_bucket/syslog /tmp/
s3://bean_bucket/syslog -> /tmp/syslog [1 of 1]
302838 of 302838 100% in 0s 16.41 MB/s done
获取bucket已使用空间
root@node2:~# s3cmd du s3://bean_bucket
302838 s3://bean_bucket/
获取bucket或者对象的stat信息
root@node2:~# s3cmd info s3://bean_bucket
s3://bean_bucket/ (bucket):
Location: any
ACL: bean_li: FULL_CONTROL
root@node2:~# s3cmd info s3://bean_bucket/syslog
s3://bean_bucket/syslog (object):
File size: 302838
Last mod: Wed, 30 Mar 2016 15:30:37 GMT
MIME type: binary/octet-stream
MD5 sum: ddd973c94c88adba8b0624c4d7711f6d
ACL: bean_li: FULL_CONTROL
算了，不浪费时间了，剩下其他功能可以自己探索了。