neondatabase/neon · warning

Unknown placement policy '{s}', try detached,secondary,attac

Error message

Unknown placement policy '{s}', try detached,secondary,attached:<n>

What it means

The placement policy parser did not recognize the value at all: it is neither the keyword 'detached' nor 'secondary' and does not start with 'attached:'. This is the catch-all FromStr error for PlacementPolicyArg.

Source

Thrown at control_plane/storcon_cli/src/main.rs:362

impl FromStr for PlacementPolicyArg {
    type Err = anyhow::Error;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        match s {
            "detached" => Ok(Self(PlacementPolicy::Detached)),
            "secondary" => Ok(Self(PlacementPolicy::Secondary)),
            _ if s.starts_with("attached:") => {
                let mut splitter = s.split(':');
                let _prefix = splitter.next().unwrap();
                match splitter.next().and_then(|s| s.parse::<usize>().ok()) {
                    Some(n) => Ok(Self(PlacementPolicy::Attached(n))),
                    None => Err(anyhow::anyhow!(
                        "Invalid format '{s}', a valid example is 'attached:1'"
                    )),
                }
            }
            _ => Err(anyhow::anyhow!(
                "Unknown placement policy '{s}', try detached,secondary,attached:<n>"
            )),
        }
    }
}

#[derive(Debug, Clone)]
struct SkSchedulingPolicyArg(SkSchedulingPolicy);

impl FromStr for SkSchedulingPolicyArg {
    type Err = anyhow::Error;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        SkSchedulingPolicy::from_str(s).map(Self)
    }
}

#[derive(Debug, Clone)]

View on GitHub (pinned to 8f60b04da4)

Solutions

1. Use exactly one of detached, secondary, or attached:<n>
2. Check for stray whitespace or quotes around the argument
3. Consult --help for the accepted policy syntax

Example fix

# before
--placement-policy attach:1
# after
--placement-policy attached:1

let arg = arg.trim();
if !matches!(arg, "detached" | "secondary") && !arg.starts_with("attached:") {
    eprintln!("unknown policy '{arg}'; try detached, secondary, attached:<n>");
}

fn is_known_placement_policy(s: &str) -> bool {
    matches!(s, "detached" | "secondary") || s.starts_with("attached:")
}

When it happens

Trigger: Typos, casing, or whitespace deviations: attach:1, Detached, ' detached' (leading space from quoting), detached-standby, or an empty string.

Common situations: Shell quoting mistakes adding whitespace, stale flag vocabulary from older CLI versions, autocomplete typos.

Related errors

• Invalid format '{s}', a valid example is 'attached:1'
• Unknown scheduling policy '{s}', try active,essential,pause,
• Unknown availability state '{s}'
• setting scheduling policy unsuccessful for safekeeper {node_
• Supply either config file path or --config=inline-config

AI-assisted analysis of neondatabase/neon@8f60b04da4 (2026-08-16). Data as JSON: /api/errors/1bff4611b7413c05. Report an issue: GitHub.