Enum Error 

#[non_exhaustive]
pub enum Error {
    Io {
        target: Option<SocketAddr>,
        source: Error,
    },
    Timeout {
        target: Option<SocketAddr>,
        elapsed: Duration,
        request_id: i32,
        retries: u32,
    },
    Snmp {
        target: Option<SocketAddr>,
        status: ErrorStatus,
        index: u32,
        oid: Option<Oid>,
    },
    InvalidOid {
        kind: OidErrorKind,
        input: Option<Box<str>>,
    },
    Decode {
        offset: usize,
        kind: DecodeErrorKind,
    },
    Encode {
        kind: EncodeErrorKind,
    },
    RequestIdMismatch {
        expected: i32,
        actual: i32,
    },
    VersionMismatch {
        expected: Version,
        actual: Version,
    },
    MessageTooLarge {
        size: usize,
        max: usize,
    },
    UnknownEngineId {
        target: Option<SocketAddr>,
    },
    NotInTimeWindow {
        target: Option<SocketAddr>,
    },
    AuthenticationFailed {
        target: Option<SocketAddr>,
        kind: AuthErrorKind,
    },
    DecryptionFailed {
        target: Option<SocketAddr>,
        kind: CryptoErrorKind,
    },
    EncryptionFailed {
        target: Option<SocketAddr>,
        kind: CryptoErrorKind,
    },
    InvalidCommunity {
        target: Option<SocketAddr>,
    },
    NonIncreasingOid {
        previous: Oid,
        current: Oid,
    },
    DuplicateOid {
        oid: Oid,
    },
    GetBulkNotSupportedInV1,
    Config(String),
}

The main error type for all async-snmp operations.

This enum covers all possible error conditions including network issues, protocol errors, encoding/decoding failures, and SNMPv3 security errors.

Common Patterns

Checking Error Type

Use pattern matching to handle specific error conditions:

use async_snmp::{Error, ErrorStatus};

fn is_retriable(error: &Error) -> bool {
    matches!(error,
        Error::Timeout { .. } |
        Error::Io { .. } |
        Error::NotInTimeWindow { .. }
    )
}

fn is_access_error(error: &Error) -> bool {
    matches!(error,
        Error::Snmp { status: ErrorStatus::NoAccess | ErrorStatus::AuthorizationError, .. } |
        Error::AuthenticationFailed { .. } |
        Error::InvalidCommunity { .. }
    )
}

Extracting Target Address

Many errors include the target address for diagnostics:

use async_snmp::Error;

fn log_error(error: &Error) {
    if let Some(addr) = error.target() {
        println!("Error from {}: {}", addr, error);
    } else {
        println!("Error: {}", error);
    }
}

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Io

I/O error during network communication.

Fields

target: Option<SocketAddr>

source: Error

Timeout

Request timed out (after retries if configured).

Fields

target: Option<SocketAddr>

elapsed: Duration

request_id: i32

retries: u32

Snmp

SNMP protocol error returned by agent.

Fields

target: Option<SocketAddr>

status: ErrorStatus

index: u32

oid: Option<Oid>

InvalidOid

Invalid OID format.

Fields

kind: OidErrorKind

input: Option<Box<str>>

Decode

BER decoding error.

Fields

offset: usize

kind: DecodeErrorKind

Encode

BER encoding error.

Fields

kind: EncodeErrorKind

RequestIdMismatch

Response request ID doesn’t match.

Fields

expected: i32

actual: i32

VersionMismatch

Response version doesn’t match request.

Fields

expected: Version

actual: Version

MessageTooLarge

Message exceeds maximum size.

Fields

size: usize

max: usize

UnknownEngineId

Unknown engine ID (SNMPv3).

Fields

target: Option<SocketAddr>

NotInTimeWindow

Message outside time window (SNMPv3).

Fields

target: Option<SocketAddr>

AuthenticationFailed

Authentication failed (SNMPv3).

Fields

target: Option<SocketAddr>

kind: AuthErrorKind

DecryptionFailed

Decryption failed (SNMPv3).

Fields

target: Option<SocketAddr>

kind: CryptoErrorKind

EncryptionFailed

Encryption failed (SNMPv3).

Fields

target: Option<SocketAddr>

kind: CryptoErrorKind

InvalidCommunity

Invalid community string.

Fields

target: Option<SocketAddr>

NonIncreasingOid

Non-increasing OID detected during walk (agent misbehavior).

Returned when a walk operation receives an OID that is not lexicographically greater than the previous OID, which would cause an infinite loop. This indicates a non-conformant SNMP agent.

Only occurs with OidOrdering::Strict (the default).

Fields

previous: Oid

current: Oid

DuplicateOid

Walk detected a cycle (same OID returned twice).

Only occurs with OidOrdering::AllowNonIncreasing, which uses a HashSet to track all seen OIDs and detect cycles.

Fields

oid: Oid

GetBulkNotSupportedInV1

GETBULK not supported in SNMPv1.

Returned when WalkMode::GetBulk is explicitly requested with an SNMPv1 client. GETBULK is only available in SNMPv2c and SNMPv3.

Config(String)

Configuration error.

Returned when client configuration is invalid (e.g., privacy without authentication, missing passwords).

Implementations

impl Error

pub fn decode(offset: usize, kind: DecodeErrorKind) -> Self

Create a decode error.

pub fn encode(kind: EncodeErrorKind) -> Self

Create an encode error.

pub fn auth(target: Option<SocketAddr>, kind: AuthErrorKind) -> Self

Create an authentication error.

pub fn decrypt(target: Option<SocketAddr>, kind: CryptoErrorKind) -> Self

Create a decryption error.

pub fn encrypt(target: Option<SocketAddr>, kind: CryptoErrorKind) -> Self

Create an encryption error.

pub fn invalid_oid(kind: OidErrorKind) -> Self

Create an invalid OID error from a kind (no input string).

pub fn invalid_oid_with_input( kind: OidErrorKind, input: impl Into<Box<str>>, ) -> Self

Create an invalid OID error with the input string that failed.

pub fn target(&self) -> Option<SocketAddr>

Get the target address if this error has one.

Returns Some(addr) for network-related errors that have a known target, None for errors like OID parsing or encoding that aren’t target-specific.

Example

use async_snmp::Error;
use std::time::Duration;

let error = Error::Timeout {
    target: Some("192.168.1.1:161".parse().unwrap()),
    elapsed: Duration::from_secs(5),
    request_id: 42,
    retries: 3,
};

assert_eq!(
    error.target().map(|a| a.to_string()),
    Some("192.168.1.1:161".to_string())
);

Trait Implementations

impl Debug for Error

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Error

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.