--- title: Synthetic monitoring response codes source: https://docs.newrelic.com/docs/synthetics/synthetic-monitoring/using-monitors/synthetic-monitoring-response-codes --- Synthetic monitors returns a number of additional response codes beyond standard HTTP response codes, visible in the [**Resources** page](https://docs.newrelic.com/docs/synthetics/new-relic-synthetics/pages/synthetics-resources-understand-load-times). These response codes are based on [Chromium's response codes](https://code.google.com/p/chromium/codesearch#chromium/src/net/base/net_error_list.h&sq=package:chromium) and give you more detail on the behavior of your monitors. ## Response codes Synthetic monitoring returns the following additional response codes: | Response Code | Definition | | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | `-2` | `net::ERR_FAILED, "Generic network error"` | | `-3` | `net::ERR_ABORTED, "An operation was aborted (due to user action)"` A Chrome-specific response code when the script hits a timeout and the runner is shutting down. To do that, the runner ends all pending requests. | | `-7` | `net::ERR_TIMED_OUT, "Timed out"` | | `-10` | `net::ERR_ACCESS_DENIED, "Access denied"` | | `-20` | `net::ERR_BLOCKED_BY_CLIENT, "Blocked"` | | `-100` | `net::ERR_CONNECTION_CLOSED, "Connection was closed (TCP FIN)"` | | `-101` | `net::ERR_CONNECTION_RESET, "Connection was reset (TCP RST)"` | | `-102` | `net::ERR_CONNECTION_REFUSED, "Connection was refused"` | | `-103` | `net::ERR_CONNECTION_ABORTED, "Connection was aborted (no ACK received)"` | | `-104` | `net::ERR_CONNECTION_FAILED, "Connection attempt failed"` | | `-105` | `net::ERR_NAME_NOT_RESOLVED, "Host name could not be resolved"` | | `-106` | `net::ERR_INTERNET_DISCONNECTED, "Internet connection lost"` | | `-107` | `net::ERR_SSL_PROTOCOL_ERROR, "SSL protocol error"` | | `-108` | `net::ERR_ADDRESS_INVALID, "Invalid IP address and/or port number"` | | `-109` | `net::ERR_ADDRESS_UNREACHABLE, "Unreachable IP address"` | | `-110` | `net::ERR_SSL_CLIENT_AUTH_CERT_NEEDED, "Server requested a client certificate for SSL client authentication"` | | `-112` | `net::ERR_NO_SSL_VERSIONS_ENABLED, "No SSL protocol versions are enabled"` | | `-113` | `net::ERR_SSL_VERSION_OR_CIPHER_MISMATCH, "Client and server don't support a common SSL protocol version or cipher suite"` | | `-114` | `net::ERR_SSL_RENEGOTIATION_REQUESTED, "Server requested a renegotiation (re-handshake)"` | | `-116` | `net::ERR_CERT_ERROR_IN_SSL_RENEGOTIATION, "During SSL renegotiation (re-handshake), the server sent a certificate with an error"` | | `-117` | `net::ERR_BAD_SSL_CLIENT_AUTH_CERT, "SSL handshake failed because of a bad or missing client certificate"` | | `-118` | `net::ERR_CONNECTION_TIMED_OUT, "Timed out"` | | `-123` | `net::ERR_SSL_NO_RENEGOTIATION, "Peer sent an SSL no_renegotiation alert message"` | | `-138` | `net::ERR_ACCESS_DENIED, "Access denied"` | | `-141` | `net::ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED, "Unable to sign the CertificateVerify data of an SSL client auth handshake with the client certificate's private key"` | | `-145` | `net::ERR_WS_PROTOCOL_ERROR, "WebSocket protocol error - connection terminated due to a malformed frame or other protocol violation"` | | `-147` | `net::ERR_ADDRESS_IN_USE, "Failed to bind to an address because already in use"` | | `-148` | `net::ERR_SSL_HANDSHAKE_NOT_COMPLETED, "SSL handshake has not completed"` | | `-149` | `net::ERR_SSL_BAD_PEER_PUBLIC_KEY, "SSL peer's public key is invalid"` | | `-150` | `net::ERR_SSL_PINNED_KEY_NOT_IN_CERT_CHAIN, "Certificate didn't match built-in public key pins for the host name"` | | `-151` | `net::ERR_CLIENT_AUTH_CERT_TYPE_UNSUPPORTED, "Server request for client certificate did not contain any types we support"` | | `-152` | `net::ERR_ORIGIN_BOUND_CERT_GENERATION_TYPE_MISMATCH, "Server requested one type of cert, then requested a different type while the first was still being generated"` | | `-153` | `net::ERR_SSL_DECRYPT_ERROR_ALERT, "SSL peer sent us a fatal decrypt_error alert"` | | `-156` | `net::ERR_SSL_SERVER_CERT_CHANGED, "SSL server certificate changed in a renegotiation"` | | `-157` | `net::ERR_SSL_INAPPROPRIATE_FALLBACK, "SSL server indicated that an unnecessary TLS version fallback was performed"` | | `-158` | `net::ERR_CT_NO_SCTS_VERIFIED_OK, "All Signed Certificate Timestamps failed to verify"` | | `-159` | `net::ERR_SSL_UNRECOGNIZED_NAME_ALERT, "SSL server sent us a fatal unrecognized_name alert"` | | `-164` | `net::ERR_SSL_CLIENT_AUTH_CERT_BAD_FORMAT, "Failed to import a client certificate from the platform store into the SSL library"` | | `-165` | `net::ERR_SSL_FALLBACK_BEYOND_MINIMUM_VERSION", "SSL server requires falling back to a version older than the configured minimum fallback version"` | | `-166` | `net::ERR_ICANN_NAME_COLLISION", "Resolving a hostname to an IP address list included the IPv4 address \"127.0.53.53\". This is a special IP address which ICANN has recommended to indicate there was a name collision, and alert admins to a potential problem"` | | `-200` | `net::ERR_CERT_COMMON_NAME_INVALID, "Server responded with a certificate whose common name did not match the host name"` | | `-201` | `net::ERR_CERT_DATE_INVALID", "Server responded with a certificate that is either expired or not valid yet"` | | `-202` | `net::ERR_CERT_AUTHORITY_INVALID, "Server responsde with a certificate signed by an untrusted authority"` | | `-203` | `net::ERR_CERT_CONTAINS_ERRORS", "Server responded with a certificate that contains errors"` | | `-204` | `net::ERR_CERT_NO_REVOCATION_MECHANISM, "Certificate has no mechanism for determining if it is revoked"` | | `-205` | `net::ERR_CERT_UNABLE_TO_CHECK_REVOCATION", "Revocation information for the security certificate for this site is not available"` | | `-206` | `net::ERR_CERT_REVOKED, "Server responded with a certificate that has been revoked"` | | `-207` | `net::ERR_CERT_INVALID, "Server responded with a certificate that is invalid"` | | `-208` | `net::ERR_CERT_WEAK_SIGNATURE_ALGORITHM, "server responded with a certificate that is signed using a weak signature algorithm"` | | `-210` | `net::ERR_CERT_NON_UNIQUE_NAME, "Host name specified in the certificate is not unique"` | | `-211` | `net::ERR_CERT_WEAK_KEY, "Server responded with a certificate that contains a weak key"` | | `-212` | `net::ERR_CERT_NAME_CONSTRAINT_VIOLATION, "Certificate claimed DNS names that are in violation of name constraints"` | | `-213` | `net::ERR_CERT_VALIDITY_TOO_LONG, "Certificate's validity period is too long"` | | `-324` | `net::ERR_EMPTY_RESPONSE, "Server closed the connection without sending any data"` | | `-803` | `net::ERR_DNS_TIMED_OUT, "DNS lookup timed out"` | | `-9999` | `"unknown error, error not mapped"` |