Detailed description of the scenario's application and purpose.

Diagnose network connectivity, upload/download bandwidth, download time, and local symlink anomalies between the local workstation and OSS using ossutil 2.0 integrated with the Alibaba Cloud CLI.

Architecture: Local Workstation + Alibaba Cloud CLI 3.3.3+ + aliyun ossutil + OSS Bucket + Optional target object or presigned URL + Optional probe domain

Scenario	Recommended Command	Output
Upload connectivity probe	`aliyun ... ossutil probe --upload`	Upload duration, object name, log file
Download connectivity probe	`aliyun ... ossutil probe --download`	Download duration, local file path, log file
Upload bandwidth suggestion	`aliyun ... ossutil probe --probe-item upload-speed`	Suggested concurrency value
Download bandwidth suggestion	`aliyun ... ossutil probe --probe-item download-speed`	Suggested concurrency value
Download time measurement	`aliyun ... ossutil probe --probe-item download-time`	Concurrency/part-size/duration statistics
Symlink anomaly check	`aliyun ... ossutil probe --probe-item cycle-symlink`	Whether abnormal symlinks exist

Important implementation boundary

probe is a composite client-side diagnostic command provided by aliyun ossutil; there is no equivalent aliyun oss api probe.

cycle-symlink can only detect abnormal symlinks — it cannot safely auto-fix target paths.

Probe output can locate symptoms and suggest concurrency, but cannot guarantee an automatic precise root cause for all network anomalies.

download-speed requires a real existing object, and the official recommendation is objects larger than 5 MiB. If no suitable object exists, the user must first confirm an existing object path, or confirm a local file to upload via aliyun ossutil cp before probing.

Installation

Pre-check: Aliyun CLI >= 3.3.3 required Run aliyun version to verify >= 3.3.3. If not installed or version too low, see references/cli-installation-guide.md for installation instructions. Then run the credential gate aliyun configure list. Only after configure list shows a valid profile, run aliyun configure set --auto-plugin-install true and aliyun ossutil version.

Run the version and credential gate first:

aliyun version
aliyun configure list

Only after configure list confirms a valid profile, proceed:

aliyun configure set --auto-plugin-install true
aliyun configure ai-mode enable
aliyun ossutil version

AI safety mode: configure ai-mode enable activates the CLI's built-in safety guard, which blocks dangerous operations (e.g. deleting critical resources) at the CLI level. This must be enabled before executing any ossutil commands.

Environment Variables

Environment Variable	Required/Optional	Description	Default Value
`ALIBABA_CLOUD_PROFILE`	Optional	Specify which CLI profile to use	Current default profile
`HTTP_PROXY`	Optional	HTTP proxy address in proxied environments	None
`HTTPS_PROXY`	Optional	HTTPS proxy address in proxied environments	None
`NO_PROXY`	Optional	Proxy bypass list	None

Parameter Confirmation

IMPORTANT: Parameter Confirmation — Before executing any command or API call, ALL user-customizable parameters (e.g., RegionId, instance names, CIDR blocks, passwords, domain names, resource specifications, etc.) MUST be confirmed with the user. Do NOT assume or use default values without explicit user approval.

Parameter Name	Required/Optional	Description	Default Value
`profile`	Optional	CLI profile to use	Current default profile
`region_id`	Optional	Region where the bucket is located; use when auto-detection is unreliable or explicit specification is needed	None
`bucket_name`	Required for bucket-based probes	Target bucket name	None
`object_name`	Required for `download-speed` and `download-time`; optional for other bucket-based probes	Full object path, e.g. `dir/example.txt`; for `download-speed`, objects larger than 5 MiB are recommended for stable results	None
`local_path`	Optional	Local upload file path, symlink scan directory, or download save path	None
`download_url`	Required for URL-based download probe	Public-read URL or signed private URL	None
`endpoint`	Optional	Use only when the user explicitly provides it or the error message clearly points to a specific endpoint	None
`addr`	Optional	Domain for `--addr` network connectivity check	`www.aliyun.com` only if user explicitly accepts
`upmode`	Optional	Upload probe mode	`normal`
`runtime`	Optional	Max runtime in seconds for `upload-speed` / `download-speed`	CLI default
`parallel`	Optional	Single-file concurrency for `download-time`	`1`
`part_size`	Optional	Part size in bytes for `download-time`	CLI auto/default

Authentication

Pre-check: Alibaba Cloud Credentials Required

Security Rules:

NEVER read, echo, or print AK/SK values (e.g., echo $ALIBABA_CLOUD_ACCESS_KEY_ID is FORBIDDEN)

NEVER ask the user to input AK/SK directly in the conversation or command line

NEVER use aliyun configure set with literal credential values

NEVER read credential files such as ~/.aliyun/config.json, or dump environment variables to inspect credentials

NEVER write a full presigned URL with query-string signature parameters into logs or final output; if you must mention it, redact everything after ?

ONLY use aliyun configure list to check credential status
aliyun configure list
Check the output for a valid profile (AK, STS, or OAuth identity).

If no valid profile exists, STOP here.

Obtain credentials from Alibaba Cloud Console

Configure credentials outside of this session (via aliyun configure in terminal or environment variables in shell profile)

Return and re-run after aliyun configure list shows a valid profile

If multiple profiles exist, explicitly add --profile <profile> in subsequent commands, placed after aliyun and before ossutil, e.g. aliyun --profile <profile> ossutil version.

RAM Policy

The minimum OSS permissions required by this skill depend on the probe mode. Refer to references/ram-polices.md for per-scenario permission tables and policy examples.

Upload probes, upload bandwidth probes, temporary object probes: require at least oss:GetObject, oss:PutObject, oss:DeleteObject
Download probes, download bandwidth probes, download time probes: require at least oss:GetObject
If using aliyun ossutil cp to pre-upload a test object: requires oss:PutObject
If using aliyun ossutil rm to clean up an explicitly specified test object: requires oss:DeleteObject

Core Workflow

1. Validate the CLI environment

Execute in the following order — do not skip steps:

Check CLI version first:

aliyun version

Then check credentials/profile:

aliyun configure list

If configure list does not show a valid profile, or reports a missing config file, STOP immediately.
- Do NOT proceed with configure set --auto-plugin-install true
- Do NOT proceed with ossutil version
- Do NOT fabricate bucket, object, profile, region, or probe success results
Only after the profile is valid, proceed to prepare the plugin, enable AI safety mode, and verify ossutil:

aliyun configure set --auto-plugin-install true
aliyun configure ai-mode enable
aliyun ossutil version

1.1 Log file naming and command substitution

When saving execution logs, use static strings for filenames (e.g. probe_download_time.log). Do not use $(date ...), $(...), or backtick shell command substitutions in filenames, because different execution environments have inconsistent shell interpolation support, which can easily cause syntax errors.
Some execution environments block $() command substitution entirely. When you need to capture command output into a variable (e.g. for presigned URLs), use the file+script pattern: redirect output to a temporary file, then create a shell script that reads the file and uses the value. See §B for a concrete example.

2. Choose the probe mode

A. Upload connectivity probe

If the user only wants network/upload connectivity diagnostics without keeping the object, omit local_path and object_name and let probe use a temporary file that is auto-cleaned after completion.
If the user wants to verify a specific real file's upload path, confirm local_path.
If the upload probe returns AccessDenied, quote the error as-is and explain that at least oss:GetObject, oss:PutObject, oss:DeleteObject are required; do not enumerate buckets, regions, or fall back to legacy command forms.

aliyun ossutil probe \
  --upload "<LOCAL_PATH_IF_ANY>" \
  --bucket "<BUCKET_NAME>" \
  --object "<OBJECT_NAME_IF_USER_WANTS_TO_KEEP_IT>" \
  --addr "<ADDR_IF_CONFIRMED>" \
  --upmode "<UPMODE_IF_CONFIRMED>" \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills

When LOCAL_PATH_IF_ANY is not provided, remove that positional parameter entirely — do not pass an empty string.

B. Download probe via URL

Public-read objects: have the user confirm a directly accessible URL.
Private objects: generate a presigned URL first, then run probe --download --url.

Generate a presigned URL, save it to a temporary file, then run the probe via a shell script. This two-step approach avoids exposing the full URL in command history and works in environments where $() command substitution is blocked.

Step 1 — Generate the presigned URL and redirect output to a temporary file:

aliyun ossutil presign \
  "oss://<BUCKET_NAME>/<OBJECT_NAME>" \
  --expires-duration 1h \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills > /tmp/_presign_url.txt

Step 2 — Create a probe script that reads the URL from the file and runs the download probe:

cat > /tmp/_run_presign_probe.sh << 'PROBE_SCRIPT'
#!/bin/bash
PRESIGN_URL=$(cat /tmp/_presign_url.txt)
aliyun ossutil probe \
  --download \
  --url "$PRESIGN_URL" \
  "<LOCAL_PATH_IF_USER_WANTS_TO_RENAME>" \
  --user-agent AlibabaCloud-Agent-Skills
PROBE_SCRIPT
bash /tmp/_run_presign_probe.sh

Important — you MUST use probe --download --url with the presigned URL:

Never copy-paste the full presigned URL directly into the --url parameter — use the file+script pattern above so the URL is never exposed in command history or execution logs.

If /tmp/ is not writable, use the current workspace directory for the temporary file and script instead.

--url only accepts HTTP/HTTPS URLs — it cannot take oss://bucket/object.

A successful ossutil presign only means the signed URL was generated; it does not guarantee the bucket or object exists, nor that the subsequent download will succeed.
If you need to log the execution, do not persist the full presigned URL; at most keep the object address without the query string, or redact all signature parameters after ?.
If probe --download --url returns 404/403, quote the raw HTTP error first; if the bucket/object was already confirmed input, you may do one ossutil stat validation with the same bucket + object + region. Do not try to "guess" the root cause by listing buckets, trying random regions, or reading local credential files.

C. Download probe via Bucket/Object

If the user confirmed object_name, the command will download that object directly.
If the user does not provide object_name, probe will create a temporary object, download it, and delete the temporary object after completion.

aliyun ossutil probe \
  --download \
  --bucket "<BUCKET_NAME>" \
  --object "<OBJECT_NAME_IF_ANY>" \
  --addr "<ADDR_IF_CONFIRMED>" \
  "<LOCAL_PATH_IF_USER_WANTS_TO_RENAME>" \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills

If the command reports NoSuchBucket, NoSuchKey, or other object-level errors, prefer running ossutil stat "oss://<BUCKET_NAME>/<OBJECT_NAME>" --region "<REGION_ID_IF_NEEDED>" for same-target validation.
Do not list all buckets, try unconfirmed regions, or switch to aliyun oss api / GetBucketLocation or other commands outside this skill's scope to confirm whether the object exists.

D. Local symlink anomaly probe

This mode only checks local directory/file paths — it does not access OSS.

aliyun ossutil probe \
  --probe-item cycle-symlink \
  "<LOCAL_DIRECTORY_OR_FILE>" \
  --user-agent AlibabaCloud-Agent-Skills

If the command returns stat <path>: no such file or directory, explicitly state that the local path does not exist in the current execution environment; this is still a local-only flow with no OSS access.
When the local path does not exist, you must NEVER:
- Interpret it as "this is a containerized/sandbox environment limitation"
- Automatically rewrite it as "the user should run on another machine/production environment"
- Generate a script file saying "run this command in the correct environment"
- Check the parent directory with ls and then give up
Correct approach: Quote the raw error stat <path>: no such file or directory, explicitly tell the user the path does not exist in the current environment, and ask whether they provided the correct path. Unless the user proactively states the current session is not on the target machine, do not make that judgment for them.

When reporting results of this probe, include at minimum:

This is a local-only flow — no OSS access occurred
Which symlinks are abnormal and which link chains were directly verified; if only partial chains can be verified, clearly distinguish "confirmed chain segments" from "anomaly points proven by probe errors", e.g. loop-b -> loop-a, and resolving loop-a reports too many levels of symbolic links
If the probe output contains raw errors, quote at least one key error, e.g. too many levels of symbolic links
Minimum fix prerequisites, e.g. break one of the cyclic links or re-point the abnormal link to a real target before retrying

If you need to clarify the abnormal link chain, you may perform read-only local forensics on the same path (e.g. readlink, stat -f "%N -> %Y"). Only write precise chains when these supplementary results are actually readable; if the supplementary forensics itself fails, report only verified segments — do not fabricate a complete cycle.

If the output lists abnormal symlinks, the user or a local script must fix them according to business semantics; this skill does not auto-rewrite symlink targets.

E. Upload bandwidth probe with suggested concurrency

Basic command:

aliyun ossutil probe \
  --probe-item upload-speed \
  --bucket "<BUCKET_NAME>" \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills

To limit runtime, add:

aliyun ossutil probe \
  --probe-item upload-speed \
  --bucket "<BUCKET_NAME>" \
  --runtime "<RUNTIME_IF_CONFIRMED>" \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills

Successful output will contain suggest parallel is <N>.

F. Download bandwidth probe with suggested concurrency

object_name is required.
Official recommendation: target object should be larger than 5 MiB.
If the user has no suitable object, first confirm a local file path, then upload a cleanable test object via aliyun ossutil cp.

Optional preparation step:

aliyun ossutil cp \
  "<LOCAL_FILE_TO_UPLOAD>" \
  "oss://<BUCKET_NAME>/<OBJECT_NAME>" \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills

Run download bandwidth probe:

aliyun ossutil probe \
  --probe-item download-speed \
  --bucket "<BUCKET_NAME>" \
  --object "<OBJECT_NAME>" \
  --runtime "<RUNTIME_IF_CONFIRMED>" \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills

G. Download time probe

Basic command:

aliyun ossutil probe \
  --probe-item download-time \
  --bucket "<BUCKET_NAME>" \
  --object "<OBJECT_NAME>" \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills

To explicitly control concurrency and part size, add:

aliyun ossutil probe \
  --probe-item download-time \
  --bucket "<BUCKET_NAME>" \
  --object "<OBJECT_NAME>" \
  --parallel "<PARALLEL_IF_CONFIRMED>" \
  --part-size "<PART_SIZE_IF_CONFIRMED>" \
  --region "<REGION_ID_IF_NEEDED>" \
  --user-agent AlibabaCloud-Agent-Skills

--parallel and --part-size are only meaningful in the download-time scenario; do not misuse them with upload-speed.

3. Interpret the output

When upload/download probes succeed, the output will contain upload file:success or download file:success
When bandwidth probes succeed, the output will contain multiple parallel:<N> statistics and suggest parallel is <N>
When download time probes succeed, the output will contain total bytes, cost, avg speed
All probe modes typically generate a logOssProbe*.log local log file; after probe execution, you must check whether logOssProbe*.log was generated in the current directory and report the log path in the final answer
If a real command returns an error or has no success marker, the final conclusion must explicitly state failure/blocked and quote the raw error message — do not write "task completed successfully" or describe a failure as successful verification
When a command fails, the final answer must explicitly state the termination reason (e.g. "stopped due to AccessDenied", "stopped due to path not found") — do not end silently
For errors like The bucket you are attempting to access must be addressed using the specified endpoint, this only means the current access endpoint does not match the bucket's requirements; stop immediately, ask the user to confirm the correct region/endpoint — do not infer or try other region/endpoints on your own

See references/verification-method.md for more detailed verification steps.

Success Verification Method

Follow the steps in references/verification-method.md to confirm each item:

CLI version and profile are valid
Probe output contains success markers or suggested concurrency
You must run ls logOssProbe*.log to check whether log files were generated locally, and report the log path in the final answer; if no log files were generated, it means the probe may not have reached the actual probing stage
If an explicit test object was used, confirm whether it should be retained or enter the cleanup step
If any of the above steps fail, the final answer must explicitly state failure and quote the raw error with termination reason

Cleanup

Upload/download connectivity probes without an explicit --object will auto-clean temporary objects
If you explicitly uploaded a test object in the download-speed preparation step, decide whether to delete it based on user confirmation after probing

Delete an OSS test object:

aliyun ossutil rm \
  "oss://<BUCKET_NAME>/<OBJECT_NAME>" \
  --user-agent AlibabaCloud-Agent-Skills

If a temporary test file was downloaded locally, it should also be deleted or retained based on user confirmation.

After all probe and cleanup steps are finished, disable AI safety mode:

aliyun configure ai-mode disable

API and Command Tables

For all commands, underlying OSS capability mappings, and which steps are local client-side logic only, see references/related-apis.md.

Best Practices

Always use aliyun ossutil probe — do not fabricate non-existent commands like aliyun oss api probe
Confirm all user-variable parameters before execution, especially bucket_name, object_name, download_url, local_path
Only retain probe objects when the user explicitly confirms; otherwise prefer temporary objects or explicit cleanup
For download-speed, choose a real object larger than 5 MiB for more stable results
In proxy, dedicated line, or custom domain scenarios, explicitly confirm --addr, --region, --endpoint
Use suggest parallel is <N> as an empirical baseline, then do small-scale validation combined with actual business concurrency
For cycle-symlink, only diagnose — do not auto-fix
After command failure, prefer same-target validation (e.g. ossutil stat) — do not expand into listing buckets, guessing regions, trying unsupported flags, or reading local credential files
Do not expose AK/SK, STS tokens, or full presigned URL query strings in logs or final results
A successful presign, resolvable DNS, or reachable ping/traceroute does not guarantee the object exists or that the probe will succeed; conclusions must be based on actual probe/validation results

Reference Links

Reference	Purpose
`references/cli-installation-guide.md`	Installing and upgrading Aliyun CLI
`references/verification-method.md`	Checking success by probe mode
`references/related-apis.md`	Command to underlying OSS capability/permission mapping
`references/ram-polices.md`	RAM permission checklist and policy examples
`references/acceptance-criteria.md`	Skill acceptance criteria and counter-examples
`references/implementation-boundaries.md`	Boundaries that cannot be fully automated via CLI or code

alibabacloud-oss-manage-network-probe