Error map
508 HTTP 508 Loop Detected (Resource Limit Is Reached)
HTTP · layer 2, Network
Centre: this error. First ring: errors it is linked with (12). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (12)
HTTP 500 Internal Server Error
The server hit an unexpected condition — usually an unhandled exception or misconfiguration in the application.
HTTP 503 Service Unavailable
The server is temporarily unable to handle the request — overloaded, in maintenance, or has no healthy backends.
HTTP 302 Found (Temporary Redirect)
The resource is temporarily at another URL; clients should keep using the original URL for future requests.
FATAL: too many connections for role "x"
The role reached its per-role CONNECTION LIMIT (often set by hosting providers or free tiers).
MySQL ERROR 1040 (08004): Too many connections
MySQL reached `max_connections` and refuses new clients.
HTTP 429 Too Many Requests
You’ve hit a rate limit — too many requests in a given time window. Slow down and retry later.
FATAL: sorry, too many clients already / remaining connection slots are reserved for non-replication superuser connections
PostgreSQL reached max_connections.
Azure: SkuNotAvailable / QuotaExceeded when creating a VM or resource
The VM size isn’t offered in that region/zone for your subscription, or you’ve hit the vCPU quota.
HTTP 301 Moved Permanently
The resource has a new permanent URL; clients and search engines should use the address in the Location header from now on.
MySQL ERROR 1114 (HY000): The table 'x' is full
MySQL couldn’t extend the table — disk full, a size limit, or a MEMORY table hitting max_heap_table_size.
ERROR: could not extend file "base/…": No space left on device
The disk holding the PostgreSQL data directory (or WAL) is full.
HTTP 509 Bandwidth Limit Exceeded
A hosting-control-panel status (cPanel/Apache) meaning the account used up its monthly bandwidth allowance.
Two steps away (33)
HTTP 404 Not Found
The server can’t find anything at the requested URL.
HTTP 502 Bad Gateway
A proxy or gateway (Nginx, load balancer, CDN) got an invalid response — or no response — from the upstream server behind it.
SyntaxError: Unexpected token < in JSON at position 0
`JSON.parse()` / `response.json()` received something that isn’t JSON — very often an HTML error page.
Kubernetes: CrashLoopBackOff
The container starts, crashes (or exits), and Kubernetes keeps restarting it with increasing back-off delays.
HTTP 504 Gateway Timeout
A proxy or gateway waited too long for the upstream server to respond and gave up.
WordPress: Briefly unavailable for scheduled maintenance. Check back in a minute.
An update was interrupted and WordPress left its `.maintenance` file behind, so the site stays in maintenance mode.
HTTP 401 Unauthorized
The request has no valid authentication credentials — you need to log in or send a valid token.
HTTP 200 OK (but something is still wrong)
The request succeeded at the HTTP level — yet the page is blank, the data is wrong, or an error is hidden inside the response bod…
HTTP 303 See Other
A redirect telling the client to fetch the result from another URL with GET — used after a form POST so refreshing doesn’t resubm…
PostgreSQL: could not connect to server / connection refused — Is the server running on host and accepting TCP/IP connections?
The client reached no PostgreSQL listener at that host/port — the server is down, listening elsewhere, or not accepting remote co…
FATAL: database "x" does not exist
The connection names a database that isn’t on that server.
server closed the connection unexpectedly — This probably means the server terminated abnormally before or while processing the request.
The connection to PostgreSQL dropped — the server restarted/crashed, a proxy/firewall killed an idle connection, or the backend w…
MySQL ERROR 2002 (HY000): Can't connect to local MySQL server through socket
The client couldn’t reach the MySQL server — it isn’t running, or the client is looking for the socket/port in the wrong place.
WordPress: Error Establishing a Database Connection
WordPress can’t connect to its MySQL/MariaDB database with the credentials in wp-config.php, or the database server is down.
Lock wait timeout exceeded; try restarting transaction (MySQL 1205)
A query waited too long for a row lock held by another transaction and gave up.
Kubernetes: ImagePullBackOff / ErrImagePull
The node can’t pull the container image — wrong name/tag, missing registry credentials, or registry unreachable.
AWS: ThrottlingException / Rate exceeded
You exceeded the request rate for an AWS API; retry with exponential backoff.
HTTP 403 Forbidden
The server understood the request but refuses to authorize it — you (or the server process) are not allowed to access this resour…
server does not support SSL, but SSL was required / no pg_hba.conf entry … no encryption
The client and server disagree about SSL — the client requires it but the server doesn’t offer it, or the server requires it and…
InsufficientInstanceCapacity: We currently do not have sufficient capacity in the Availability Zone you requested
AWS has no free capacity for that instance type in that Availability Zone right now.
Azure VM: AllocationFailed / ZonalAllocationFailed — Allocation failed. We do not have sufficient capacity for the requested VM size
Azure has no capacity for that VM size in the region/zone (or in the cluster the VM is pinned to) right now.
Azure: AuthorizationFailed — The client does not have authorization to perform action
The signed-in identity (user, service principal or managed identity) lacks an Azure RBAC role for that action on that scope.
VcpuLimitExceeded: You have requested more vCPU capacity than your current vCPU limit
Your account’s On-Demand (or Spot) vCPU quota for that instance family and region is used up.
HTTP 402 Payment Required
The service wants payment before it will process the request — an unpaid invoice, exhausted credits or a failed card.
HTTP 410 Gone
The resource used to exist but was intentionally and permanently removed, with no forwarding address.
Cloudflare Error 520: Web Server Returned an Unknown Error
Cloudflare connected to your origin, but the origin returned an empty, unknown or invalid response.
HTTP 304 Not Modified
The cached copy is still valid, so the server sends no body and the client reuses its cache.
no space left on device (Docker / Linux)
The disk (or inode table) is full — Docker images, build cache, logs and volumes are common culprits.
Azure Storage: AuthorizationPermissionMismatch (403) — This request is not authorized to perform this operation using this permission
You’re accessing blob/queue data with Microsoft Entra ID, but the identity has only management roles (Owner/Contributor) — not a…
MySQL ERROR 126 (HY000): Incorrect key file for table; try to repair it
MySQL can’t use a table’s index file — usually a full tmp disk during a query, or MyISAM corruption.
StorageAccountAlreadyTaken: The storage account named x is already taken
Storage account names are globally unique across Azure; another customer (or you elsewhere) already uses the name.
Azure Storage: Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature (AuthenticationFailed)
The storage request’s signature or SAS token is invalid — wrong/rotated account key, expired SAS, or clock skew.
Azure Storage: ContainerNotFound / BlobNotFound — The specified container (or blob) does not exist
The container or blob path doesn’t exist in that storage account.
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