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Patrick Debois

Downloading - Uploading to a Vsphere Datastore

In previous blogposts I’ve setup a fresh Vmware ESX Server and Created an ISO file for an Ubuntu Automated Install .

To be able to boot a new Virtual Machine from this isofile, we first need to make it available in a Datastore on the server:

  1. The first option is to use the Vsphere Client to upload the file, but that would not be much of an automation
  2. An alternative is to use scp to transfer files to the vsphere server. The datastore typically resides under /vmfs/volumes/
  3. Since ESX 3.5 , there is a third way by uploading files over http. This is the option we will further explore

The theory:

HTTP Access to vSphere Server Files is described in Appendix C of the programming guide - PDF that you can download from the VMware vSphere Web Services SDK Documentation .

To access a file store you would use a URL like this

http-method http[s]://server/folder[[/path]?dcPath=path[&dsName=name]]

where:

  • dsName : name of the datastore, datastore1 on a standard installation
  • dcPath: name of the datacenter, ha-datacenter on a standard installation
  • path: a path under your datastore
  • folder: this is a special prefix to indicate that we are doing datastore access. For config files you would use /config instead of folder.

With this URL, you would use the different methods GET, HEAD, PUT, or DELETE to interface with it.

The practice, problem…

I found a simple shell script describing the uploading via curl at http://blogs.vmware.com/esxi/2010/01/scripting-datastore-access.html

When I execute that script against my ESX 4.1, the script would just hang. No http error, just hang.

I found a mention of someone with a similar problem . Apparently this worked in 4.0 but something had changed in 4.1

Debugging the problem:

I started interfacing directly with curl now. –insecure to overcome the self-signed certificate

$ curl -H "Expect:" -v --insecure --upload-file myiso.iso "https:root:password@192.168.2.240/folder/myiso.iso?dcPath=ha-datacenter&dsName=datastore1" 
* About to connect() to 192.168.2.240 port 443 (#0)
*   Trying 192.168.2.240... connected
* Connected to 192.168.2.240 (192.168.2.240) port 443 (#0)
* SSLv3, TLS handshake, Client hello (1):
* SSLv3, TLS handshake, Server hello (2):
* SSLv3, TLS handshake, CERT (11):
* SSLv3, TLS handshake, Server finished (14):
* SSLv3, TLS handshake, Client key exchange (16):
* SSLv3, TLS change cipher, Client hello (1):
* SSLv3, TLS handshake, Finished (20):
* SSLv3, TLS change cipher, Client hello (1):
* SSLv3, TLS handshake, Finished (20):
* SSL connection using AES256-SHA
* Server certificate:
* 	 subject: C=US; ST=California; L=Palo Alto; O=VMware, Inc; OU=VMware ESX Server Default Certificate; emailAddress=ssl-certificates@vmware.com; CN=esx4-server.example.org; unstructuredName=1288860765,564d7761726520496e632e
* 	 start date: 2010-11-04 08:52:45 GMT
* 	 expire date: 2022-05-05 08:52:45 GMT
* 	 common name: esx4-server.example.org (does not match '192.168.2.240')
* 	 issuer: O=VMware Installer
* 	 SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.
* Server auth using Basic with user 'root'
> PUT /folder/myiso.iso?dcPath=ha-datacenter&dsName=datastore1 HTTP/1.1
> Authorization: Basic cm9vdDpwaXBvcG8=
> User-Agent: curl/7.19.7 (universal-apple-darwin10.0) libcurl/7.19.7 OpenSSL/0.9.8l zlib/1.2.3
> Host: 192.168.2.240
> Accept: */*
> Content-Length: 205
> Expect: 100-continue

And here it hung. I first thought that it was because it used the Expect: 100-continue, so I tried to disable it.

curl -H "Expect:" -v --insecure --upload-file myiso.iso "https:root:password@192.168.2.240/folder/myiso.iso?dcPath=ha-datacenter&dsName=datastore1" 

And also using HTTP/1.0

curl -0 -H -v --insecure --upload-file myiso.iso "https:root:password@192.168.2.240/folder/myiso.iso?dcPath=ha-datacenter&dsName=datastore1" 

To see what was happening on the server side, I looked at /var/log/vmware/hostd.log :

[2010-12-11 15:17:35.128 F5CEEB90 verbose 'DatastoreBrowser'] 4cd2736b-38881d7a-d86d-000c29350f64-datastorebrowser::Search Path = [datastore1] Spec = (vim.host.DatastoreBrowser.SearchSpec) {
 dynamicType = <unset>, 
 query = (vim.host.DatastoreBrowser.Query) [
    (vim.host.DatastoreBrowser.FolderQuery) {
       dynamicType = <unset>, 
    }, 
    (vim.host.DatastoreBrowser.Query) {
       dynamicType = <unset>, 
    }
 ], 
 details = (vim.host.DatastoreBrowser.FileInfo.Details) {
    dynamicType = <unset>, 
    fileType = true, 
    fileSize = false, 
    modification = false, 
    fileOwner = false, 
 }, 
 searchCaseInsensitive = <unset>, 
 matchPattern = (string) [
    "      "myiso\.iso"
 ], 
 sortFoldersFirst = <unset>, 
}
[2010-12-11 15:17:35.128 F5CEEB90 verbose 'DatastoreBrowser'] 4cd2736b-38881d7a-d86d-000c29350f64-datastorebrowser::SearchInt
[2010-12-11 15:17:35.128 F5CEEB90 verbose 'DatastoreBrowser'] 4cd2736b-38881d7a-d86d-000c29350f64-datastorebrowser::GetLocalpathFromDatastorepath
[2010-12-11 15:17:35.129 F5CEEB90 verbose 'DatastoreBrowser'] 4cd2736b-38881d7a-d86d-000c29350f64-datastorebrowser::Verify
[2010-12-11 15:17:35.130 F5CEEB90 error 'App'] AdapterServer caught exception: 5e38fb28
[2010-12-11 15:17:35.130 F5CEEB90 error 'App'] Backtrace:

After re-reading the blogpost mentioning the problem, someone mentioned that in the Vsphere 4.1 Vmware CLI documentation it stated the following:

--put | -p <local_path> <remote_path>
Uploads a file from the machine on which you run the vCLI commands to the ESX/ESXi host. This operation uses HTTP PUT. This command can replace existing host files but cannot create new files.

By experimenting I found out that the HTTP API can not upload to the root folder of a datastore. Hmm, but the API did not mention anything about creating a directory, only uploading files. When the subdirectory was created, the curl command would work perfectly.

[2010-12-11 16:32:40.335 F54A5B90 verbose 'DatastoreBrowser'] 4cd2736b-38881d7a-d86d-000c29350f64-datastorebrowser::SearchInt
[2010-12-11 16:32:40.335 F54A5B90 verbose 'DatastoreBrowser'] 4cd2736b-38881d7a-d86d-000c29350f64-datastorebrowser::GetLocalpathFromDatastorepath
[2010-12-11 16:32:40.336 F54A5B90 verbose 'DatastoreBrowser'] 4cd2736b-38881d7a-d86d-000c29350f64-datastorebrowser::Verify
[2010-12-11 16:32:40.362 F5360B90 verbose 'HttpSvc.HTTPService'] HTTP Response: Complete (processed 0 bytes)
[2010-12-11 16:32:40.362 F5360B90 verbose 'HttpSvc.HTTPService'] User agent is 'VMware VI Client/4.0.0'
[2010-12-11 16:32:40.362 F5360B90 verbose 'HttpSvc.HTTPService'] HTTP Response: Client: NeedsContentLength: false UnderstandsChunking: true CanKeepAlive: true (PresetContentLength 0)

Solving the problem:

Luckily TIMTOWTD (There’s more than one way to do it) was on my side!

Introducing the Mob API

The creation of directories can be done through the Mob API which I remember from the article http://www.doublecloud.org/2010/02/introducing-a-tiny-yet-powerful-api-to-manage-and-automate-vsphere/ .

He also mentioned a Vijava rest interface to use it . To see a sample check out http:vijava.svn.sourceforge.net/viewvc/vijava/trunk/src/com/vmware/vim/rest/sample/RestAppDemo.java?view=markup

You can connect to the Mob API using your browser with the URL https:///mob . This gives you a very nice interface to execute things on your server.

Create Directories To make a directory you would post to

https://192.168.2.240/mob/?moid=ha%2dnfc%2dfile%2dmanager&method=makeDirectory

and POST the the form parameters:

name=[datastore1] isodir
datacenter=<datacenter type="Datacenter" xsi:type="ManagedObjectReference">ha-datacenter</datacenter>
createParentDirectories=true

Remove Files Similarly you can use it do delete a file, execute a POST to

https://192.168.2.240/mob/?moid=ha%2dnfc%2dfile%2dmanager&method=deleteFile

with the following form params

name=[datastore1] isodir/myiso.iso
datacenter=<datacenter type="Datacenter" xsi:type="ManagedObjectReference">ha-datacenter</datacenter>