diff --git a/Cargo.lock b/Cargo.lock
index 7a133d5af03..47ac15b35b9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -8875,6 +8875,7 @@ dependencies = [
  "nexus-db-schema",
  "nexus-inventory",
  "nexus-lockstep-client",
+ "nexus-networking",
  "nexus-reconfigurator-preparation",
  "nexus-saga-recovery",
  "nexus-test-utils",
@@ -8907,6 +8908,7 @@ dependencies = [
  "steno",
  "strum 0.27.2",
  "subprocess",
+ "support-bundle-collection",
  "support-bundle-viewer",
  "supports-color 3.0.2",
  "tabled 0.15.0",
@@ -8919,6 +8921,7 @@ dependencies = [
  "url",
  "uuid",
  "vergen-gitcl",
+ "zip 4.6.1",
 ]
 
 [[package]]
diff --git a/dev-tools/omdb/Cargo.toml b/dev-tools/omdb/Cargo.toml
index 27de5c27917..3ecacb60934 100644
--- a/dev-tools/omdb/Cargo.toml
+++ b/dev-tools/omdb/Cargo.toml
@@ -19,6 +19,7 @@ base64.workspace = true
 bootstrap-agent-lockstep-client.workspace = true
 bytes.workspace = true
 camino.workspace = true
+camino-tempfile.workspace = true
 chrono.workspace = true
 clap.workspace = true
 clickhouse-admin-single-client.workspace = true
@@ -54,6 +55,7 @@ nexus-db-queries.workspace = true
 nexus-db-schema.workspace = true
 nexus-inventory.workspace = true
 nexus-lockstep-client.workspace = true
+nexus-networking.workspace = true
 nexus-reconfigurator-preparation.workspace = true
 nexus-saga-recovery.workspace = true
 nexus-types.workspace = true
@@ -83,6 +85,7 @@ slog.workspace = true
 slog-error-chain.workspace = true
 steno.workspace = true
 strum.workspace = true
+support-bundle-collection.workspace = true
 support-bundle-viewer.workspace = true
 supports-color.workspace = true
 tabled.workspace = true
@@ -104,6 +107,7 @@ nexus-test-utils-macros.workspace = true
 omicron-nexus.workspace = true
 omicron-test-utils.workspace = true
 subprocess.workspace = true
+zip.workspace = true
 
 # Disable doc builds by default for our binaries to work around issue
 # rust-lang/cargo#8373.  These docs would not be very useful anyway.
diff --git a/dev-tools/omdb/src/bin/omdb/main.rs b/dev-tools/omdb/src/bin/omdb/main.rs
index 8d3524e96a7..ca8df0783ee 100644
--- a/dev-tools/omdb/src/bin/omdb/main.rs
+++ b/dev-tools/omdb/src/bin/omdb/main.rs
@@ -58,6 +58,7 @@ mod oxql;
 mod reconfigurator;
 mod sled_agent;
 mod support_bundle;
+mod support_bundle_collect;
 
 fn main() -> Result<(), anyhow::Error> {
     sigpipe::reset();
@@ -83,6 +84,7 @@ async fn main_impl() -> Result<(), anyhow::Error> {
             reconfig.run_cmd(&args, &log).await
         }
         OmdbCommands::SledAgent(sled) => sled.run_cmd(&args, &log).await,
+        OmdbCommands::SupportBundle(sb) => sb.run_cmd(&args, &log).await,
         OmdbCommands::CrucibleAgent(crucible) => crucible.run_cmd(&args).await,
         OmdbCommands::CruciblePantry(crucible) => crucible.run_cmd(&args).await,
         OmdbCommands::ClickhouseAdmin(ch) => ch.run_cmd(&args, &log).await,
@@ -297,6 +299,8 @@ enum OmdbCommands {
     Reconfigurator(reconfigurator::ReconfiguratorArgs),
     /// Debug a specific Sled
     SledAgent(sled_agent::SledAgentArgs),
+    /// Collect or inspect a support bundle
+    SupportBundle(support_bundle_collect::SupportBundleArgs),
 }
 
 fn parse_dropshot_log_level(
diff --git a/dev-tools/omdb/src/bin/omdb/support_bundle_collect.rs b/dev-tools/omdb/src/bin/omdb/support_bundle_collect.rs
new file mode 100644
index 00000000000..0a7a0af2d9a
--- /dev/null
+++ b/dev-tools/omdb/src/bin/omdb/support_bundle_collect.rs
@@ -0,0 +1,221 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+//! `omdb support-bundle collect` — collect a support bundle locally,
+//! without going through Nexus.
+//!
+//! Unlike the Nexus background task, this path:
+//!
+//! - Does not register a row in the `support_bundle` table.
+//! - Does not transfer the resulting bundle to a sled-agent for durable
+//!   storage. The zip is written to a local file path.
+//! - Does not require Nexus to be up. It only needs CRDB, internal
+//!   DNS, MGS, and the rack's sled-agents reachable on the underlay.
+//!
+//! This is intended for incident response, where the operator may need
+//! to collect a bundle precisely because Nexus is unhealthy.
+
+use crate::Omdb;
+use crate::db::DbUrlOptions;
+use anyhow::Context;
+use camino::Utf8PathBuf;
+use camino_tempfile::tempdir_in;
+use clap::Args;
+use clap::Subcommand;
+use clap::ValueEnum;
+use nexus_db_queries::context::OpContext;
+use nexus_db_queries::db::DataStore;
+use nexus_types::fm::ereport::EreportFilters;
+use nexus_types::support_bundle::BundleDataSelection;
+use omicron_uuid_kinds::SupportBundleUuid;
+use std::io::Seek;
+use std::io::SeekFrom;
+use std::sync::Arc;
+use support_bundle_collection::BundleCollection;
+use support_bundle_collection::BundleInfo;
+use support_bundle_collection::zip::bundle_to_zipfile;
+
+/// Categories of data the bundle collector knows how to gather.
+///
+/// Mirrors `nexus_types::support_bundle::BundleDataCategory`, but is
+/// declared here so it can derive `clap::ValueEnum` without making
+/// `nexus-types` depend on clap.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, ValueEnum)]
+enum BundleCategory {
+    Reconfigurator,
+    HostInfo,
+    SledCubbyInfo,
+    SpDumps,
+    Ereports,
+}
+
+/// Arguments to the "omdb support-bundle" subcommand
+#[derive(Debug, Args)]
+pub struct SupportBundleArgs {
+    #[command(subcommand)]
+    command: SupportBundleCommands,
+}
+
+#[derive(Debug, Subcommand)]
+enum SupportBundleCommands {
+    /// Collect a support bundle without involving Nexus.
+    ///
+    /// Connects directly to CockroachDB, internal DNS, MGS, and the
+    /// rack's sled-agents — none of which depend on Nexus being up.
+    /// The bundle is written to a local zip file. No row is created
+    /// in the `support_bundle` table.
+    Collect(CollectArgs),
+}
+
+#[derive(Debug, Args)]
+struct CollectArgs {
+    #[command(flatten)]
+    db_url_opts: DbUrlOptions,
+
+    /// Path where the resulting bundle zip will be written.
+    #[clap(long, short = 'o')]
+    output: Utf8PathBuf,
+
+    /// Reason recorded inside the bundle's metadata.
+    #[clap(long, default_value = "collected via omdb")]
+    reason: String,
+
+    /// Directory to use for staging the bundle contents before zipping.
+    #[clap(long, default_value = "/var/tmp")]
+    tempdir: Utf8PathBuf,
+
+    /// Categories of data to collect. May be supplied multiple times.
+    /// Defaults to all categories.
+    #[clap(long, value_enum)]
+    include: Vec<BundleCategory>,
+}
+
+impl CollectArgs {
+    fn data_selection(&self) -> BundleDataSelection {
+        let categories: &[BundleCategory] = if self.include.is_empty() {
+            BundleCategory::value_variants()
+        } else {
+            self.include.as_slice()
+        };
+
+        let mut sel = BundleDataSelection::new();
+        for category in categories {
+            sel = match category {
+                BundleCategory::Reconfigurator => sel.with_reconfigurator(),
+                BundleCategory::HostInfo => sel.with_all_sleds(),
+                BundleCategory::SledCubbyInfo => sel.with_sled_cubby_info(),
+                BundleCategory::SpDumps => sel.with_sp_dumps(),
+                BundleCategory::Ereports => sel.with_ereports(
+                    EreportFilters::new()
+                        .with_start_time(
+                            omicron_common::now_db_precision()
+                                - chrono::Days::new(7),
+                        )
+                        .expect("no end time set, cannot fail"),
+                ),
+            };
+        }
+        sel
+    }
+}
+
+impl SupportBundleArgs {
+    pub async fn run_cmd(
+        &self,
+        omdb: &Omdb,
+        log: &slog::Logger,
+    ) -> anyhow::Result<()> {
+        match &self.command {
+            SupportBundleCommands::Collect(args) => args.run(omdb, log).await,
+        }
+    }
+}
+
+impl CollectArgs {
+    async fn run(&self, omdb: &Omdb, log: &slog::Logger) -> anyhow::Result<()> {
+        self.db_url_opts
+            .with_datastore(omdb, log, async |opctx, datastore| {
+                self.collect(omdb, log, opctx, datastore).await
+            })
+            .await
+    }
+
+    async fn collect(
+        &self,
+        omdb: &Omdb,
+        log: &slog::Logger,
+        opctx: OpContext,
+        datastore: Arc<DataStore>,
+    ) -> anyhow::Result<()> {
+        let resolver = omdb.dns_resolver(log.clone()).await?;
+
+        let bundle = BundleInfo {
+            id: SupportBundleUuid::new_v4(),
+            reason_for_creation: self.reason.clone(),
+        };
+        let bundle_log = log.new(slog::o!("bundle" => bundle.id.to_string()));
+        eprintln!("Collecting support bundle {}", bundle.id);
+
+        let collection = Arc::new(BundleCollection::new(
+            datastore,
+            resolver,
+            bundle_log,
+            opctx,
+            self.data_selection(),
+            bundle,
+        ));
+
+        // Wire Ctrl-C to cancel the in-flight collection.
+        let cancel_handle = tokio::spawn({
+            let token = collection.cancellation_token().clone();
+            async move {
+                let _ = tokio::signal::ctrl_c().await;
+                eprintln!("\nCtrl-C received — cancelling bundle collection.");
+                token.cancel();
+            }
+        });
+
+        let dir = tempdir_in(&self.tempdir).with_context(|| {
+            format!("creating temp dir under {}", self.tempdir)
+        })?;
+        let collect_result = collection.collect_bundle_locally(&dir).await;
+        cancel_handle.abort();
+        let _ = cancel_handle.await;
+        let report = collect_result?;
+
+        let zip_tempdir = self.tempdir.clone();
+        let output = self.output.clone();
+        tokio::task::spawn_blocking(move || -> anyhow::Result<()> {
+            let mut tempfile = bundle_to_zipfile(&dir, &zip_tempdir)?;
+            tempfile.seek(SeekFrom::Start(0))?;
+            let mut out = std::fs::File::create(&output)
+                .with_context(|| format!("creating {output}"))?;
+            std::io::copy(&mut tempfile, &mut out)?;
+            Ok(())
+        })
+        .await
+        .context("zip task panicked")??;
+
+        eprintln!("Wrote bundle to {}", self.output);
+        eprintln!("{} steps executed:", report.steps.len());
+        for step in &report.steps {
+            let dur = step.end - step.start;
+            eprintln!(
+                "  {:>9}ms  {:?}  {}",
+                dur.num_milliseconds(),
+                step.status,
+                step.name,
+            );
+        }
+        if let Some(ereports) = &report.ereports {
+            eprintln!(
+                "ereports: {} found, {} collected, {} errors",
+                ereports.n_found,
+                ereports.n_collected,
+                ereports.errors.len(),
+            );
+        }
+        Ok(())
+    }
+}
diff --git a/dev-tools/omdb/tests/test_all_output.rs b/dev-tools/omdb/tests/test_all_output.rs
index b787dceefd9..0dd1b55843f 100644
--- a/dev-tools/omdb/tests/test_all_output.rs
+++ b/dev-tools/omdb/tests/test_all_output.rs
@@ -436,6 +436,51 @@ async fn test_omdb_success_cases() {
     );
     assert!(!parsed.collections.is_empty());
 
+    // Exercise `omdb support-bundle collect` end-to-end. We don't add this
+    // to the `successes.out` snapshot because the output includes a
+    // randomly-generated bundle UUID, timing-dependent step durations,
+    // and per-sled step names that would all need redaction. Instead we
+    // run the command and verify the resulting zip is well-formed and
+    // contains the expected metadata files.
+    let bundle_path = tmpdir.path().join("bundle.zip");
+    let bundle_args: &[&str] = &[
+        "support-bundle",
+        "collect",
+        "--output",
+        bundle_path.as_str(),
+        "--tempdir",
+        tmpdir.path().as_str(),
+        "--reason",
+        "integration test",
+    ];
+    let mut bundle_output = String::new();
+    let p = postgres_url.clone();
+    let dns = cptestctx.internal_dns.dns_server.local_address().to_string();
+    do_run_no_redactions(
+        &mut bundle_output,
+        move |exec| exec.env("OMDB_DB_URL", &p).env("OMDB_DNS_SERVER", &dns),
+        &cmd_path,
+        bundle_args,
+    )
+    .await;
+    let zip_file = std::fs::File::open(&bundle_path).unwrap_or_else(|err| {
+        panic!(
+            "bundle zip not produced at {bundle_path}: {}\n\
+             omdb output was:\n{bundle_output}",
+            InlineErrorChain::new(&err),
+        )
+    });
+    let mut archive =
+        zip::ZipArchive::new(zip_file).expect("bundle is a valid zip archive");
+    for required in
+        ["bundle_id.txt", "meta/reason_for_creation.txt", "meta/trace.json"]
+    {
+        assert!(
+            archive.by_name(required).is_ok(),
+            "bundle zip is missing expected entry {required}",
+        );
+    }
+
     let ox_invocation = &["oximeter", "list-producers"];
     let mut ox_output = String::new();
     let ox = ox_url.clone();
diff --git a/dev-tools/omdb/tests/usage_errors.out b/dev-tools/omdb/tests/usage_errors.out
index b940a1f991f..db57bc2686c 100644
--- a/dev-tools/omdb/tests/usage_errors.out
+++ b/dev-tools/omdb/tests/usage_errors.out
@@ -19,6 +19,7 @@ Commands:
   oxql              Enter the Oximeter Query Language shell for interactive querying
   reconfigurator    Interact with the Reconfigurator system
   sled-agent        Debug a specific Sled
+  support-bundle    Collect or inspect a support bundle
   help              Print this message or the help of the given subcommand(s)
 
 Options:
@@ -54,6 +55,7 @@ Commands:
   oxql              Enter the Oximeter Query Language shell for interactive querying
   reconfigurator    Interact with the Reconfigurator system
   sled-agent        Debug a specific Sled
+  support-bundle    Collect or inspect a support bundle
   help              Print this message or the help of the given subcommand(s)
 
 Options: