diff --git a/compute_tools/src/compute.rs b/compute_tools/src/compute.rs
index c591d9711a..9744cc2dac 100644
--- a/compute_tools/src/compute.rs
+++ b/compute_tools/src/compute.rs
@@ -217,6 +217,46 @@ pub struct ParsedSpec {
     pub endpoint_storage_token: Option<String>,
 }
 
+impl ParsedSpec {
+    pub fn validate(&self) -> Result<(), String> {
+        // Only Primary nodes are using safekeeper_connstrings, and at the moment
+        // this method only validates that part of the specs.
+        if self.spec.mode != ComputeMode::Primary {
+            return Ok(());
+        }
+
+        // While it seems like a good idea to check for an odd number of entries in
+        // the safekeepers connection string, changes to the list of safekeepers might
+        // incur appending a new server to a list of 3, in which case a list of 4
+        // entries is okay in production.
+        //
+        // Still we want unique entries, and at least one entry in the vector
+        if self.safekeeper_connstrings.is_empty() {
+            return Err(String::from("safekeeper_connstrings is empty"));
+        }
+
+        // check for uniqueness of the connection strings in the set
+        let mut connstrings = self.safekeeper_connstrings.clone();
+
+        connstrings.sort();
+        let mut previous = &connstrings[0];
+
+        for current in connstrings.iter().skip(1) {
+            // duplicate entry?
+            if current == previous {
+                return Err(format!(
+                    "duplicate entry in safekeeper_connstrings: {}!",
+                    current,
+                ));
+            }
+
+            previous = current;
+        }
+
+        Ok(())
+    }
+}
+
 impl TryFrom<ComputeSpec> for ParsedSpec {
     type Error = String;
     fn try_from(spec: ComputeSpec) -> Result<Self, String> {
@@ -246,6 +286,7 @@ impl TryFrom<ComputeSpec> for ParsedSpec {
         } else {
             spec.safekeeper_connstrings.clone()
         };
+
         let storage_auth_token = spec.storage_auth_token.clone();
         let tenant_id: TenantId = if let Some(tenant_id) = spec.tenant_id {
             tenant_id
@@ -280,7 +321,7 @@ impl TryFrom<ComputeSpec> for ParsedSpec {
             .clone()
             .or_else(|| spec.cluster.settings.find("neon.endpoint_storage_token"));
 
-        Ok(ParsedSpec {
+        let res = ParsedSpec {
             spec,
             pageserver_connstr,
             safekeeper_connstrings,
@@ -289,7 +330,11 @@ impl TryFrom<ComputeSpec> for ParsedSpec {
             timeline_id,
             endpoint_storage_addr,
             endpoint_storage_token,
-        })
+        };
+
+        // Now check validity of the parsed specification
+        res.validate()?;
+        Ok(res)
     }
 }
 
@@ -2342,3 +2387,21 @@ impl<T: 'static> JoinSetExt<T> for tokio::task::JoinSet<T> {
         })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use std::fs::File;
+
+    use super::*;
+
+    #[test]
+    fn duplicate_safekeeper_connstring() {
+        let file = File::open("tests/cluster_spec.json").unwrap();
+        let spec: ComputeSpec = serde_json::from_reader(file).unwrap();
+
+        match ParsedSpec::try_from(spec.clone()) {
+            Ok(_p) => panic!("Failed to detect duplicate entry"),
+            Err(e) => assert!(e.starts_with("duplicate entry in safekeeper_connstrings:")),
+        };
+    }
+}
diff --git a/compute_tools/tests/README.md b/compute_tools/tests/README.md
new file mode 100644
index 0000000000..adeb9ef4b6
--- /dev/null
+++ b/compute_tools/tests/README.md
@@ -0,0 +1,6 @@
+### Test files
+
+The file `cluster_spec.json` has been copied over from libs/compute_api
+tests, with some edits:
+
+  - the neon.safekeepers setting contains a duplicate value
diff --git a/compute_tools/tests/cluster_spec.json b/compute_tools/tests/cluster_spec.json
new file mode 100644
index 0000000000..5655a94de4
--- /dev/null
+++ b/compute_tools/tests/cluster_spec.json
@@ -0,0 +1,245 @@
+{
+  "format_version": 1.0,
+
+  "timestamp": "2021-05-23T18:25:43.511Z",
+  "operation_uuid": "0f657b36-4b0f-4a2d-9c2e-1dcd615e7d8b",
+
+  "cluster": {
+    "cluster_id": "test-cluster-42",
+    "name": "Zenith Test",
+    "state": "restarted",
+    "roles": [
+      {
+        "name": "postgres",
+        "encrypted_password": "6b1d16b78004bbd51fa06af9eda75972",
+        "options": null
+      },
+      {
+        "name": "alexk",
+        "encrypted_password": null,
+        "options": null
+      },
+      {
+        "name": "zenith \"new\"",
+        "encrypted_password": "5b1d16b78004bbd51fa06af9eda75972",
+        "options": null
+      },
+      {
+        "name": "zen",
+        "encrypted_password": "9b1d16b78004bbd51fa06af9eda75972"
+      },
+      {
+        "name": "\"name\";\\n select 1;",
+        "encrypted_password": "5b1d16b78004bbd51fa06af9eda75972"
+      },
+      {
+        "name": "MyRole",
+        "encrypted_password": "5b1d16b78004bbd51fa06af9eda75972"
+      }
+    ],
+    "databases": [
+      {
+        "name": "DB2",
+        "owner": "alexk",
+        "options": [
+          {
+            "name": "LC_COLLATE",
+            "value": "C",
+            "vartype": "string"
+          },
+          {
+            "name": "LC_CTYPE",
+            "value": "C",
+            "vartype": "string"
+          },
+          {
+            "name": "TEMPLATE",
+            "value": "template0",
+            "vartype": "enum"
+          }
+        ]
+      },
+      {
+        "name": "zenith",
+        "owner": "MyRole"
+      },
+      {
+        "name": "zen",
+        "owner": "zen"
+      }
+    ],
+    "settings": [
+      {
+        "name": "fsync",
+        "value": "off",
+        "vartype": "bool"
+      },
+      {
+        "name": "wal_level",
+        "value": "logical",
+        "vartype": "enum"
+      },
+      {
+        "name": "hot_standby",
+        "value": "on",
+        "vartype": "bool"
+      },
+      {
+        "name": "prewarm_lfc_on_startup",
+        "value": "off",
+        "vartype": "bool"
+      },
+      {
+        "name": "neon.safekeepers",
+        "value": "127.0.0.1:6502,127.0.0.1:6503,127.0.0.1:6501,127.0.0.1:6502",
+        "vartype": "string"
+      },
+      {
+        "name": "wal_log_hints",
+        "value": "on",
+        "vartype": "bool"
+      },
+      {
+        "name": "log_connections",
+        "value": "on",
+        "vartype": "bool"
+      },
+      {
+        "name": "shared_buffers",
+        "value": "32768",
+        "vartype": "integer"
+      },
+      {
+        "name": "port",
+        "value": "55432",
+        "vartype": "integer"
+      },
+      {
+        "name": "max_connections",
+        "value": "100",
+        "vartype": "integer"
+      },
+      {
+        "name": "max_wal_senders",
+        "value": "10",
+        "vartype": "integer"
+      },
+      {
+        "name": "listen_addresses",
+        "value": "0.0.0.0",
+        "vartype": "string"
+      },
+      {
+        "name": "wal_sender_timeout",
+        "value": "0",
+        "vartype": "integer"
+      },
+      {
+        "name": "password_encryption",
+        "value": "md5",
+        "vartype": "enum"
+      },
+      {
+        "name": "maintenance_work_mem",
+        "value": "65536",
+        "vartype": "integer"
+      },
+      {
+        "name": "max_parallel_workers",
+        "value": "8",
+        "vartype": "integer"
+      },
+      {
+        "name": "max_worker_processes",
+        "value": "8",
+        "vartype": "integer"
+      },
+      {
+        "name": "neon.tenant_id",
+        "value": "b0554b632bd4d547a63b86c3630317e8",
+        "vartype": "string"
+      },
+      {
+        "name": "max_replication_slots",
+        "value": "10",
+        "vartype": "integer"
+      },
+      {
+        "name": "neon.timeline_id",
+        "value": "2414a61ffc94e428f14b5758fe308e13",
+        "vartype": "string"
+      },
+      {
+        "name": "shared_preload_libraries",
+        "value": "neon",
+        "vartype": "string"
+      },
+      {
+        "name": "synchronous_standby_names",
+        "value": "walproposer",
+        "vartype": "string"
+      },
+      {
+        "name": "neon.pageserver_connstring",
+        "value": "host=127.0.0.1 port=6400",
+        "vartype": "string"
+      },
+      {
+        "name": "test.escaping",
+        "value": "here's a backslash \\ and a quote ' and a double-quote \" hooray",
+        "vartype": "string"
+      }
+    ]
+  },
+  "delta_operations": [
+    {
+      "action": "delete_db",
+      "name": "zenith_test"
+    },
+    {
+      "action": "rename_db",
+      "name": "DB",
+      "new_name": "DB2"
+    },
+    {
+      "action": "delete_role",
+      "name": "zenith2"
+    },
+    {
+      "action": "rename_role",
+      "name": "zenith new",
+      "new_name": "zenith \"new\""
+    }
+  ],
+  "remote_extensions": {
+    "library_index": {
+      "postgis-3": "postgis",
+      "libpgrouting-3.4": "postgis",
+      "postgis_raster-3": "postgis",
+      "postgis_sfcgal-3": "postgis",
+      "postgis_topology-3": "postgis",
+      "address_standardizer-3": "postgis"
+    },
+    "extension_data": {
+      "postgis": {
+        "archive_path": "5834329303/v15/extensions/postgis.tar.zst",
+        "control_data": {
+          "postgis.control": "# postgis extension\ncomment = ''PostGIS geometry and geography spatial types and functions''\ndefault_version = ''3.3.2''\nmodule_pathname = ''$libdir/postgis-3''\nrelocatable = false\ntrusted = true\n",
+          "pgrouting.control": "# pgRouting Extension\ncomment = ''pgRouting Extension''\ndefault_version = ''3.4.2''\nmodule_pathname = ''$libdir/libpgrouting-3.4''\nrelocatable = true\nrequires = ''plpgsql''\nrequires = ''postgis''\ntrusted = true\n",
+          "postgis_raster.control": "# postgis_raster extension\ncomment = ''PostGIS raster types and functions''\ndefault_version = ''3.3.2''\nmodule_pathname = ''$libdir/postgis_raster-3''\nrelocatable = false\nrequires = postgis\ntrusted = true\n",
+          "postgis_sfcgal.control": "# postgis topology extension\ncomment = ''PostGIS SFCGAL functions''\ndefault_version = ''3.3.2''\nrelocatable = true\nrequires = postgis\ntrusted = true\n",
+          "postgis_topology.control": "# postgis topology extension\ncomment = ''PostGIS topology spatial types and functions''\ndefault_version = ''3.3.2''\nrelocatable = false\nschema = topology\nrequires = postgis\ntrusted = true\n",
+          "address_standardizer.control": "# address_standardizer extension\ncomment = ''Used to parse an address into constituent elements. Generally used to support geocoding address normalization step.''\ndefault_version = ''3.3.2''\nrelocatable = true\ntrusted = true\n",
+          "postgis_tiger_geocoder.control": "# postgis tiger geocoder extension\ncomment = ''PostGIS tiger geocoder and reverse geocoder''\ndefault_version = ''3.3.2''\nrelocatable = false\nschema = tiger\nrequires = ''postgis,fuzzystrmatch''\nsuperuser= false\ntrusted = true\n",
+          "address_standardizer_data_us.control": "# address standardizer us dataset\ncomment = ''Address Standardizer US dataset example''\ndefault_version = ''3.3.2''\nrelocatable = true\ntrusted = true\n"
+        }
+      }
+    },
+    "custom_extensions": [],
+    "public_extensions": ["postgis"]
+  },
+  "pgbouncer_settings": {
+    "default_pool_size": "42",
+    "pool_mode": "session"
+  }
+}
diff --git a/test_runner/regress/test_compute_reconfigure.py b/test_runner/regress/test_compute_reconfigure.py
index b533d45b1e..cc792333ba 100644
--- a/test_runner/regress/test_compute_reconfigure.py
+++ b/test_runner/regress/test_compute_reconfigure.py
@@ -9,6 +9,8 @@ from fixtures.utils import wait_until
 if TYPE_CHECKING:
     from fixtures.neon_fixtures import NeonEnv
 
+from fixtures.log_helper import log
+
 
 def test_compute_reconfigure(neon_simple_env: NeonEnv):
     """
@@ -85,3 +87,57 @@ def test_compute_reconfigure(neon_simple_env: NeonEnv):
     samples = metrics.query_all("compute_ctl_up", {"build_tag": build_tag})
     assert len(samples) == 1
     assert samples[0].value == 1
+
+
+def test_compute_safekeeper_connstrings_duplicate(neon_simple_env: NeonEnv):
+    """
+    Test that we catch duplicate entries in neon.safekeepers.
+    """
+    env = neon_simple_env
+
+    endpoint = env.endpoints.create_start("main")
+
+    # grab the current value of neon.safekeepers
+    sk_list = []
+    with endpoint.cursor() as cursor:
+        cursor.execute("SHOW neon.safekeepers;")
+        row = cursor.fetchone()
+        assert row is not None
+
+        log.info(f'    initial neon.safekeepers: "{row}"')
+
+        # build a safekeepers list with a duplicate
+        sk_list.append(row[0])
+        sk_list.append(row[0])
+
+    safekeepers = ",".join(sk_list)
+    log.info(f'reconfigure neon.safekeepers: "{safekeepers}"')
+
+    # introduce duplicate entry in neon.safekeepers, on purpose
+    endpoint.respec_deep(
+        **{
+            "spec": {
+                "skip_pg_catalog_updates": True,
+                "cluster": {
+                    "settings": [
+                        {
+                            "name": "neon.safekeepers",
+                            "vartype": "string",
+                            "value": safekeepers,
+                        }
+                    ]
+                },
+            },
+        }
+    )
+
+    try:
+        endpoint.reconfigure()
+
+        # Check that in logs we see that it was actually reconfigured,
+        # not restarted or something else.
+        endpoint.log_contains("INFO request{method=POST uri=/configure")
+
+    except Exception as e:
+        # we except a failure here
+        log.info(f"RAISED: {e}" % e)