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encyclopedia
Index of common CLI error messages. grep for your error below.
$
All
AWS
Ansible
Apt
Bash
Database
Docker
GPG
Git
Homebrew
Kubernetes
Linux
Network
Nginx
Node.js
OpenSSL
Python
RPM
Redis
SSH
Terraform
AWS
AWS
An error occurred (Throttling): Rate exceeded
An error occurred (Throttling) when calling the PutObject operation: Rate exceeded
->
You are making too many requests per second to the AWS API.
AWS
An error occurred (AccessDenied)
An error occurred (AccessDenied) when calling the ListBuckets operation: User: arn:aws:iam::123456789012:user/dev is not authorized to perform: s3:ListAllMyBuckets
->
Your AWS credentials are valid, but the IAM user or role does not have permission to perform the requested action.
AWS
An error occurred (ExpiredToken)
An error occurred (ExpiredToken) when calling the GetCallerIdentity operation: The security token included in the request is expired
->
Your temporary security credentials (usually from `aws sts get-session-token` or a role assumption) have expired.
AWS
An error occurred (ResourceNotFoundException)
An error occurred (ResourceNotFoundException) when calling the GetFunction operation: Requested resource not found
->
The AWS resource you are trying to access (Lambda function, DynamoDB table, etc.) does not exist in the region you are querying.
AWS
An error occurred (ValidationError)
An error occurred (ValidationError) when calling the CreateStack operation: Template format error: JSON not well-formed
->
The parameters you sent to the AWS API are invalid (wrong format, missing required fields, etc.).
Ansible
Ansible
UNREACHABLE!
192.168.1.50 | UNREACHABLE! => { "changed": false, "msg": "Failed to connect to the host via ssh: ssh: connect to host ... port 22: Connection refused", "unreachable": true }
->
Ansible could not establish an SSH connection to the target host.
Ansible
AnsibleUndefinedVariable: '...' is undefined
fatal: [localhost]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'my_var' is undefined"}
->
You are referencing a variable in a template or task that hasn't been set.
Apt
Apt
E: Could not get lock /var/lib/dpkg/lock
E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable)
->
Another process is currently using the APT package management system (e.g., an automatic update or another terminal window running apt).
Apt
E: Unable to locate package
E: Unable to locate package docker-ce
->
APT cannot find the package you requested in its current list of repositories.
Apt
E: Hash Sum mismatch
E: Hash Sum mismatch Hashes of expected file: - SHA256:...
->
The downloaded package file is corrupted or doesn't match the metadata (often due to caching proxies or bad mirrors).
Bash
Bash
syntax error near unexpected token
bash: syntax error near unexpected token `('
->
Bash encountered a character or keyword in a place it didn't expect.
Bash
Bad substitution
bash: ${var//search/replace}: bad substitution
->
You are trying to use a parameter expansion feature that `sh` (or an older bash version) doesn't support.
Bash
command not found
bash: foobar: command not found
->
The shell cannot find the executable you are trying to run in your PATH.
Database
Database
psql: error: FATAL: password authentication failed
psql: error: FATAL: password authentication failed for user "postgres"
->
PostgreSQL rejected the connection because the password provided for the user is incorrect or missing.
Database
ERROR 1045 (28000): Access denied for user
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
->
MySQL/MariaDB rejected the login attempt, usually due to an incorrect password or insufficient permissions for the host.
Database
psql: could not connect to server: No such file
psql: error: could not connect to server: No such file or directory Is the server running locally and accepting connections on Unix domain socket "/tmp/.s.PGSQL.5432"?
->
The PostgreSQL client cannot find the Unix domain socket file, usually because the server is not running or is configured to use a different socket directory.
Docker
Docker
Cannot connect to the Docker daemon
Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
->
The Docker client cannot communicate with the Docker daemon (engine).
Docker
conflict: unable to delete image
Error response from daemon: conflict: unable to delete 4c108a8 (must be forced) - image is being used by stopped container 8b12345
->
You cannot delete an image because it is still being used (even if just referenced) by a container.
Docker
exec format error
standard_init_linux.go:211: exec user process caused "exec format error"
->
The container image's architecture (e.g., ARM64) does not match the host machine's architecture (e.g., AMD64).
Docker
manifest for ... not found
Error response from daemon: manifest for node:100-alpine not found: manifest unknown
->
The requested image tag does not exist in the Docker registry.
Docker
Error response from daemon: network ... not found
Error response from daemon: network my-app-net not found
->
You are trying to start a container attached to a Docker network that doesn't exist.
Docker
docker: open /var/run/docker.sock: permission denied
docker: Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock: Post http://%2Fvar%2Frun%2Fdocker.sock/v1.24/containers/create: dial unix /var/run/docker.sock: connect: permission denied
->
Your user does not have permission to talk to the Docker daemon via the Unix socket.
Docker
Error response: Container is not running
Error response from daemon: Container 8b12345abcdef is not running
->
You are trying to execute a command (like `exec` or `stop`) on a container that is already stopped or exited.
GPG
GPG
gpg: decryption failed: No secret key
gpg: decryption failed: No secret key
->
You are trying to decrypt a message, but you don't possess the private key corresponding to the public key that encrypted it.
Git
Git
fatal: not a git repository
fatal: not a git repository (or any of the parent directories): .git
->
You are running a git command outside of a git repository.
Git
remote: error: hook declined
remote: error: hook declined to update refs/heads/main
->
A pre-receive hook on the server side rejected your push.
Git
error: failed to push some refs
error: failed to push some refs to '
[email protected]
:user/repo.git'
->
Your push was rejected because the remote repository has changes that you don't have locally.
Git
fatal: refusing to merge unrelated histories
fatal: refusing to merge unrelated histories
->
Git refuses to merge two projects that don't share a common ancestor.
Git
error: Your local changes would be overwritten by merge
error: Your local changes to the following files would be overwritten by merge: package.json
->
You have uncommitted changes in files that the merge (or pull) needs to update.
Git
fatal: ambiguous argument ... unknown revision
fatal: ambiguous argument 'feature/new-ui': unknown revision or path not in the working tree.
->
Git cannot find the branch, commit hash, or tag you specified.
Git
fatal: The current branch has no upstream branch
fatal: The current branch feature/login has no upstream branch. To push the current branch and set the remote as upstream, use git push --set-upstream origin feature/login
->
You are trying to push a new local branch that doesn't exist on the remote server yet, so Git doesn't know where to push it.
Git
fatal: could not read from remote repository
fatal: could not read from remote repository. Please make sure you have the correct access rights and the repository exists.
->
Git cannot access the remote URL, either because it doesn't exist or you lack permission.
Git
error: pathspec ... did not match any file
error: pathspec 'folder/missing.txt' did not match any file(s) known to git
->
You are trying to operate on a file or branch that Git doesn't know about.
Git
error: checkout: updating paths is incompatible
error: checkout: updating paths is incompatible with switching branches. Did you intend to checkout 'feature/branch' which can not be resolved as commit?
->
You tried to switch branches while also specifying a file path, or the branch name you provided is invalid/ambiguous.
Git
error: RPC failed; curl 56 OpenSSL SSL_read
error: RPC failed; curl 56 OpenSSL SSL_read: Connection was reset, errno 10054
->
The connection to the remote git server was dropped while transferring data, usually due to a large push/pull.
Homebrew
Homebrew
Error: Permission denied @ dir_s_mkdir
Error: Permission denied @ dir_s_mkdir - /usr/local/Frameworks
->
Homebrew lacks the necessary permissions to create a directory in a system path.
Homebrew
Error: No available formula
Error: No available formula with the name "python3.9"
->
Homebrew cannot find the package (formula) you are trying to install.
Kubernetes
Kubernetes
ImagePullBackOff
Status: ImagePullBackOff
->
Kubernetes failed to pull the container image and is backing off (waiting) before trying again.
Kubernetes
CrashLoopBackOff
Status: CrashLoopBackOff
->
The container is starting but then crashing repeatedly. Kubernetes is waiting between restarts.
Kubernetes
Error from server (Forbidden): user cannot list resource
Error from server (Forbidden): pods is forbidden: User "dev-user" cannot list resource "pods" in API group "" in the namespace "default"
->
Your Kubernetes user or service account does not have the RBAC permissions to perform the requested action.
Kubernetes
nodes is forbidden: node cannot modify node
nodes "node-1" is forbidden: node "node-1" is not allowed to modify node "node-1"
->
A Kubelet on a node is trying to modify its own Node object but lacks permission (Node Restriction admission plugin).
Kubernetes
The connection to the server localhost:8080 was refused
The connection to the server localhost:8080 was refused - did you specify the right host or port?
->
Kubectl is trying to connect to a local cluster (default behavior) but cannot find one, usually because the kubeconfig file is missing or not loaded.
Kubernetes
CreateContainerConfigError
Status: CreateContainerConfigError
->
Kubernetes failed to generate the configuration needed to start the container, often due to missing Secrets or ConfigMaps.
Kubernetes
Pod status: Pending
Status: Pending
->
The Pod has been accepted by the cluster but cannot be scheduled onto a node.
Linux
Linux
No space left on device
cp: error writing 'file': No space left on device
->
The disk partition is full, or the filesystem has run out of inodes.
Linux
Too many open files
Error: accept tcp [::]:80: accept4: too many open files
->
The process or the system has reached the limit of open file descriptors.
Linux
Permission denied
bash: /usr/local/bin/script: Permission denied
->
You do not have the required permissions (read, write, or execute) for the file or directory.
Linux
Bus error (core dumped)
./my-program: Bus error (core dumped)
->
The process tried to access a memory address that the hardware cannot physically address (often alignment issues or non-existent memory).
Linux
Segmentation fault (core dumped)
./script: Segmentation fault (core dumped)
->
The process tried to access a memory segment that it doesn't have permission to access (e.g., writing to read-only memory, dereferencing a null pointer).
Linux
File exists
mkdir: cannot create directory 'folder': File exists
->
You are trying to create a file or directory that already exists.
Linux
Read-only file system
touch: cannot touch 'file': Read-only file system
->
The filesystem is mounted as read-only, preventing any modifications.
Linux
Broken pipe
write error: Broken pipe
->
A process tried to write data to a pipe, but the process on the receiving end had already closed it.
Linux
No such file or directory
cat: config.json: No such file or directory
->
The path you specified does not exist.
Linux
User is not in the sudoers file
user is not in the sudoers file. This incident will be reported.
->
Your user account does not have administrative privileges granted via the `/etc/sudoers` file.
Linux
tar: Error is not recoverable
tar: Error is not recoverable: exiting now
->
The `tar` command encountered a critical error, often due to file corruption or incorrect compression flags.
Linux
chmod: Operation not permitted
chmod: changing permissions of '/etc/hosts': Operation not permitted
->
You are trying to change permissions of a file you don't own, or a file on a filesystem that doesn't support permissions (like FAT32/NTFS mount).
Linux
find: paths must precede expression
find: paths must precede expression: my_file.txt
->
The syntax of your `find` command is incorrect; specifically, the order of arguments is wrong.
Linux
grep: Is a directory
grep: my_folder: Is a directory
->
You asked `grep` to search a directory without telling it to be recursive.
Linux
rm: cannot remove directory: Directory not empty
rm: cannot remove 'my_folder': Directory not empty
->
You tried to remove a directory using `rmdir` or `rm` without the recursive flag, but it contains files.
Linux
umount: target is busy
umount: /mnt/data: target is busy.
->
You cannot unmount the filesystem because a process is currently using it (has an open file or current working directory there).
Linux
Failed to start service: Unit not found
Failed to start nginx.service: Unit nginx.service not found.
->
Systemd cannot find the service file you are trying to manage.
Network
Network
curl: (7) Failed to connect: Connection refused
curl: (7) Failed to connect to localhost port 8080: Connection refused
->
The target host exists but is not listening on the specified port, or a firewall is actively rejecting the connection.
Network
curl: (6) Could not resolve host
curl: (6) Could not resolve host: non-existent-domain.com
->
The DNS resolution failed; the client could not translate the hostname into an IP address.
Network
curl: (35) OpenSSL SSL_connect: SSL_ERROR_SYSCALL
curl: (35) OpenSSL SSL_connect: SSL_ERROR_SYSCALL in connection to example.com:443
->
The SSL handshake failed abruptly, often due to a firewall blocking the handshake or a proxy issue.
Network
wget: unable to resolve host address
wget: unable to resolve host address 'example.com'
->
Similar to curl's host resolution error, `wget` cannot find the IP address for the given domain.
Nginx
Nginx
nginx: [emerg] bind() failed: Address already in use
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
->
Nginx cannot start because port 80 (or 443) is already occupied by another process.
Node.js
Node.js
EADDRINUSE: address already in use
Error: listen EADDRINUSE: address already in use :::3000
->
The port you are trying to bind to is already being used by another process.
Node.js
FATAL ERROR: JavaScript heap out of memory
FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory
->
The Node.js process has exhausted its allocated memory limit (default is around 1.5GB on 64-bit systems).
Node.js
ReferenceError: ... is not defined
ReferenceError: myVar is not defined
->
You are trying to use a variable that hasn't been declared or is out of scope.
Node.js
npm ERR! code ERESOLVE
npm ERR! code ERESOLVE npm ERR! ERESOLVE unable to resolve dependency tree
->
NPM cannot find a valid set of versions for your dependencies that satisfies all constraints (peer dependency conflict).
Node.js
npm ERR! code EACCES
npm ERR! code EACCES npm ERR! syscall access npm ERR! path /usr/lib/node_modules
->
NPM does not have permission to write to the directories it needs to install packages (usually global modules).
Node.js
npm ERR! 404 Not Found
npm ERR! 404 Not Found - GET https://registry.npmjs.org/non-existent-package - Not found
->
The package or version you are trying to install does not exist in the NPM registry.
Node.js
Error: Cannot find module
Error: Cannot find module 'express'
->
Node.js cannot find the required file or package.
Node.js
node:internal/modules/cjs/loader throw err
node:internal/modules/cjs/loader:936 throw err; Error: Cannot find module ...
->
Internal Node.js loader error, usually accompanying a 'Cannot find module' error, but can also indicate corrupted internal state or version mismatch.
Node.js
npm ERR! cb() never called
npm ERR! cb() never called!
->
An internal logic error occurred within NPM, often due to race conditions or cache corruption.
OpenSSL
OpenSSL
openssl: Error: invalid command
openssl: Error: 'cert' is an invalid command.
->
You typed a subcommand that OpenSSL doesn't recognize.
Python
Python
IndentationError: unexpected indent
IndentationError: unexpected indent
->
Python found an indentation level that doesn't match the expectation.
Python
ModuleNotFoundError: No module named
ModuleNotFoundError: No module named 'pandas'
->
Python cannot locate the library you are trying to import.
Python
TypeError: object is not subscriptable
TypeError: 'NoneType' object is not subscriptable
->
You are trying to access an item using square brackets `[]` (like a list or dict) on an object that doesn't support it (like `None`, `int`, or `float`).
Python
ImportError: cannot import name
ImportError: cannot import name 'my_func' from 'my_module'
->
Python found the module but cannot find the specific function or class you are trying to import from it.
Python
ValueError: not enough values to unpack
ValueError: not enough values to unpack (expected 3, got 2)
->
You tried to unpack a sequence (list/tuple) into variables, but the number of items didn't match.
Python
SyntaxError: invalid syntax
SyntaxError: invalid syntax
->
The code violates Python's grammar rules.
Python
KeyError
KeyError: 'my_key'
->
You tried to access a dictionary key that doesn't exist.
Python
AttributeError: object has no attribute
AttributeError: 'NoneType' object has no attribute 'get'
->
You are trying to access a variable or method that doesn't exist on the object.
RPM
RPM
rpm: error: Failed dependencies
rpm: error: Failed dependencies: libc.so.6 is needed by ...
->
You are trying to install a `.rpm` file manually, but it requires other packages that are not installed.
Redis
Redis
READONLY You can't write against a read only replica
READONLY You can't write against a read only replica.
->
You are trying to execute a write command (SET, DEL, etc.) on a Redis instance that is configured as a read-only replica (slave).
SSH
SSH
Permission denied (publickey)
user@host: Permission denied (publickey).
->
The SSH server rejected your connection because it could not authenticate your public key.
SSH
Connection refused (SSH)
ssh: connect to host example.com port 22: Connection refused
->
The SSH client could not establish a TCP connection to the server on port 22.
SSH
ssh: connect to host ... port 22: Connection timed out
ssh: connect to host 192.168.1.100 port 22: Connection timed out
->
The SSH client could not reach the server within the allotted time, likely due to networking issues or a firewall dropping packets.
SSH
Host key verification failed
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! ... Host key verification failed.
->
The host key stored in your `known_hosts` file doesn't match the key provided by the server.
SSH
Received disconnect: Too many authentication failures
Received disconnect from 1.2.3.4 port 22: 2: Too many authentication failures
->
The server disconnected you because your client attempted to authenticate too many times (usually with many different keys from an agent).
SSH
sign_and_send_pubkey: signing failed
sign_and_send_pubkey: signing failed: agent refused operation Permission denied (publickey).
->
The SSH agent is running but refused to sign the authentication request, often due to file permission issues or a corrupted agent state.
SSH
kex_exchange_identification: Connection reset
kex_exchange_identification: read: Connection reset by peer
->
The SSH connection was established, but the server closed it immediately during the initial handshake (Key Exchange).
SSH
ssh: Could not resolve hostname
ssh: Could not resolve hostname my-server: Name or service not known
->
The SSH client cannot translate the hostname you provided into an IP address.
Terraform
Terraform
Error acquiring the state lock
Error acquiring the state lock Error message: 2 errors occurred: * Resource '...' does not have attribute 'id' * Resource '...' does not have attribute 'type'
->
Another process (or a previous crashed process) is holding a lock on the Terraform state file to prevent corruption.
Terraform
Failed to query available provider packages
Error: Failed to query available provider packages Could not retrieve the list of available versions for provider hashicorp/aws: no available releases match the given constraints
->
Terraform cannot find a provider version that matches the constraints in your `versions.tf` or `required_providers` block.