diff --git a/clients/client-core/src/config/mod.rs b/clients/client-core/src/config/mod.rs
index 30da8b2242..75acaf1d2e 100644
--- a/clients/client-core/src/config/mod.rs
+++ b/clients/client-core/src/config/mod.rs
@@ -26,7 +26,7 @@ pub mod persistence;
 pub const MISSING_VALUE: &str = "MISSING VALUE";
 
 // 'CLIENT'
-const DEFAULT_VALIDATOR_REST_ENDPOINT: &str = "https://directory.nymtech.net";
+pub const DEFAULT_VALIDATOR_REST_ENDPOINT: &str = "https://validator.nymtech.net";
 
 // 'DEBUG'
 const DEFAULT_ACK_WAIT_MULTIPLIER: f64 = 1.5;
@@ -176,7 +176,7 @@ impl<T: NymConfig> Config<T> {
         self.client.gateway_listener = gateway_listener.into();
     }
 
-    pub fn with_custom_validator<S: Into<String>>(&mut self, validator: S) {
+    pub fn set_custom_validator<S: Into<String>>(&mut self, validator: S) {
         self.client.validator_rest_url = validator.into();
     }
 
@@ -335,8 +335,7 @@ pub struct Client<T> {
     id: String,
 
     /// URL to the validator server for obtaining network topology.
-    // before 0.9.0 this was the directory server
-    #[serde(alias = "directory_server")]
+    #[serde(default = "missing_string_value")]
     validator_rest_url: String,
 
     /// Special mode of the system such that all messages are sent as soon as they are received
diff --git a/clients/native/src/commands/mod.rs b/clients/native/src/commands/mod.rs
index 848780729b..6523653c36 100644
--- a/clients/native/src/commands/mod.rs
+++ b/clients/native/src/commands/mod.rs
@@ -21,7 +21,7 @@ pub(crate) mod upgrade;
 
 pub(crate) fn override_config(mut config: Config, matches: &ArgMatches) -> Config {
     if let Some(validator) = matches.value_of("validator") {
-        config.get_base_mut().with_custom_validator(validator);
+        config.get_base_mut().set_custom_validator(validator);
     }
 
     if let Some(gateway_id) = matches.value_of("gateway") {
diff --git a/clients/native/src/commands/upgrade.rs b/clients/native/src/commands/upgrade.rs
index dca5c6038e..391d832faa 100644
--- a/clients/native/src/commands/upgrade.rs
+++ b/clients/native/src/commands/upgrade.rs
@@ -14,6 +14,7 @@
 
 use crate::client::config::{Config, MISSING_VALUE};
 use clap::{App, Arg, ArgMatches};
+use client_core::config::DEFAULT_VALIDATOR_REST_ENDPOINT;
 use config::NymConfig;
 use std::fmt::Display;
 use std::process;
@@ -79,12 +80,27 @@ fn pre_090_upgrade(from: &str, mut config: Config) -> Config {
         Version::new(0, 9, 0)
     };
 
+    if config.get_base().get_validator_rest_endpoint() != MISSING_VALUE {
+        eprintln!("existing config seems to have specified new validator rest endpoint which was only introduced in 0.9.0! Can't perform upgrade.");
+        print_failed_upgrade(&from_version, &to_version);
+        process::exit(1);
+    }
+
     print_start_upgrade(&from_version, &to_version);
 
     config
         .get_base_mut()
         .set_custom_version(to_version.to_string().as_ref());
 
+    println!(
+        "Setting validator REST endpoint to to {}",
+        DEFAULT_VALIDATOR_REST_ENDPOINT
+    );
+
+    config
+        .get_base_mut()
+        .set_custom_validator(DEFAULT_VALIDATOR_REST_ENDPOINT);
+
     config.save_to_file(None).unwrap_or_else(|err| {
         eprintln!("failed to overwrite config file! - {:?}", err);
         print_failed_upgrade(&from_version, &to_version);
diff --git a/clients/socks5/src/commands/mod.rs b/clients/socks5/src/commands/mod.rs
index 30be2d00ba..ef75167f5b 100644
--- a/clients/socks5/src/commands/mod.rs
+++ b/clients/socks5/src/commands/mod.rs
@@ -21,7 +21,7 @@ pub(crate) mod upgrade;
 
 pub(crate) fn override_config(mut config: Config, matches: &ArgMatches) -> Config {
     if let Some(validator) = matches.value_of("validator") {
-        config.get_base_mut().with_custom_validator(validator);
+        config.get_base_mut().set_custom_validator(validator);
     }
 
     if let Some(gateway_id) = matches.value_of("gateway") {
diff --git a/clients/socks5/src/commands/upgrade.rs b/clients/socks5/src/commands/upgrade.rs
index 8415c52162..75e58790ad 100644
--- a/clients/socks5/src/commands/upgrade.rs
+++ b/clients/socks5/src/commands/upgrade.rs
@@ -14,6 +14,7 @@
 
 use crate::client::config::{Config, MISSING_VALUE};
 use clap::{App, Arg, ArgMatches};
+use client_core::config::DEFAULT_VALIDATOR_REST_ENDPOINT;
 use config::NymConfig;
 use std::fmt::Display;
 use std::process;
@@ -79,12 +80,27 @@ fn pre_090_upgrade(from: &str, mut config: Config) -> Config {
         Version::new(0, 9, 0)
     };
 
+    if config.get_base().get_validator_rest_endpoint() != MISSING_VALUE {
+        eprintln!("existing config seems to have specified new validator rest endpoint which was only introduced in 0.9.0! Can't perform upgrade.");
+        print_failed_upgrade(&from_version, &to_version);
+        process::exit(1);
+    }
+
     print_start_upgrade(&from_version, &to_version);
 
     config
         .get_base_mut()
         .set_custom_version(to_version.to_string().as_ref());
 
+    println!(
+        "Setting validator REST endpoint to to {}",
+        DEFAULT_VALIDATOR_REST_ENDPOINT
+    );
+
+    config
+        .get_base_mut()
+        .set_custom_validator(DEFAULT_VALIDATOR_REST_ENDPOINT);
+
     config.save_to_file(None).unwrap_or_else(|err| {
         eprintln!("failed to overwrite config file! - {:?}", err);
         print_failed_upgrade(&from_version, &to_version);
diff --git a/gateway/src/commands/upgrade.rs b/gateway/src/commands/upgrade.rs
index c736eea653..bd1ab0e72b 100644
--- a/gateway/src/commands/upgrade.rs
+++ b/gateway/src/commands/upgrade.rs
@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use crate::config::DEFAULT_VALIDATOR_REST_ENDPOINT;
 use crate::config::{Config, MISSING_VALUE};
 use clap::{App, Arg, ArgMatches};
 use config::NymConfig;
@@ -81,7 +82,20 @@ fn pre_090_upgrade(from: &str, config: Config) -> Config {
 
     print_start_upgrade(&from_version, &to_version);
 
-    let upgraded_config = config.with_custom_version(to_version.to_string().as_ref());
+    if config.get_validator_rest_endpoint() != MISSING_VALUE {
+        eprintln!("existing config seems to have specified new validator rest endpoint which was only introduced in 0.9.0! Can't perform upgrade.");
+        print_failed_upgrade(&from_version, &to_version);
+        process::exit(1);
+    }
+
+    println!(
+        "Setting validator REST endpoint to to {}",
+        DEFAULT_VALIDATOR_REST_ENDPOINT
+    );
+
+    let upgraded_config = config
+        .with_custom_version(to_version.to_string().as_ref())
+        .with_custom_validator(DEFAULT_VALIDATOR_REST_ENDPOINT);
 
     upgraded_config.save_to_file(None).unwrap_or_else(|err| {
         eprintln!("failed to overwrite config file! - {:?}", err);
diff --git a/gateway/src/config/mod.rs b/gateway/src/config/mod.rs
index 5c1b8447a6..16c092c4ec 100644
--- a/gateway/src/config/mod.rs
+++ b/gateway/src/config/mod.rs
@@ -32,7 +32,7 @@ pub(crate) const MISSING_VALUE: &str = "MISSING VALUE";
 // 'GATEWAY'
 const DEFAULT_MIX_LISTENING_PORT: u16 = 1789;
 const DEFAULT_CLIENT_LISTENING_PORT: u16 = 9000;
-pub(crate) const DEFAULT_VALIDATOR_REST_ENDPOINT: &str = "https://directory.nymtech.net";
+pub(crate) const DEFAULT_VALIDATOR_REST_ENDPOINT: &str = "https://validator.nymtech.net";
 
 // 'DEBUG'
 // where applicable, the below are defined in milliseconds
@@ -494,7 +494,7 @@ pub struct Gateway {
     public_sphinx_key_file: PathBuf,
 
     /// Validator server to which the node will be reporting their presence data.
-    #[serde(alias = "presence_directory_server")]
+    #[serde(default = "missing_string_value")]
     validator_rest_url: String,
 
     /// nym_home_directory specifies absolute path to the home nym gateways directory.
diff --git a/mixnode/src/commands/upgrade.rs b/mixnode/src/commands/upgrade.rs
index 89c7374e8c..5666b3c0ee 100644
--- a/mixnode/src/commands/upgrade.rs
+++ b/mixnode/src/commands/upgrade.rs
@@ -12,7 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use crate::config::{missing_string_value, Config, DEFAULT_METRICS_SERVER};
+use crate::config::{
+    missing_string_value, Config, DEFAULT_METRICS_SERVER, DEFAULT_VALIDATOR_REST_ENDPOINT,
+};
 use clap::{App, Arg, ArgMatches};
 use config::NymConfig;
 use crypto::asymmetric::identity;
@@ -94,16 +96,27 @@ fn pre_090_upgrade(from: &str, config: Config) -> Config {
     }
 
     if config.get_metrics_server() != missing_string_value::<String>() {
-        eprintln!("existing config seems to have specified new  metrics-server endpoint which was only introduced in 0.9.0! Can't perform upgrade.");
+        eprintln!("existing config seems to have specified new metrics-server endpoint which was only introduced in 0.9.0! Can't perform upgrade.");
+        print_failed_upgrade(&from_version, &to_version);
+        process::exit(1);
+    }
+
+    if config.get_validator_rest_endpoint() != missing_string_value::<String>() {
+        eprintln!("existing config seems to have specified new validator rest endpoint which was only introduced in 0.9.0! Can't perform upgrade.");
         print_failed_upgrade(&from_version, &to_version);
         process::exit(1);
     }
 
     let mut upgraded_config = config
         .with_custom_version(to_version.to_string().as_ref())
-        .with_custom_metrics_server(DEFAULT_METRICS_SERVER);
+        .with_custom_metrics_server(DEFAULT_METRICS_SERVER)
+        .with_custom_validator(DEFAULT_VALIDATOR_REST_ENDPOINT);
 
     println!("Setting metrics server to {}", DEFAULT_METRICS_SERVER);
+    println!(
+        "Setting validator REST endpoint to to {}",
+        DEFAULT_VALIDATOR_REST_ENDPOINT
+    );
 
     println!("Generating new identity...");
     let identity_keys = identity::KeyPair::new();
diff --git a/mixnode/src/config/mod.rs b/mixnode/src/config/mod.rs
index 6996a09336..5fb44bfbb6 100644
--- a/mixnode/src/config/mod.rs
+++ b/mixnode/src/config/mod.rs
@@ -31,7 +31,7 @@ pub(crate) const MISSING_VALUE: &str = "MISSING VALUE";
 
 // 'MIXNODE'
 const DEFAULT_LISTENING_PORT: u16 = 1789;
-pub(crate) const DEFAULT_VALIDATOR_REST_ENDPOINT: &str = "https://directory.nymtech.net";
+pub(crate) const DEFAULT_VALIDATOR_REST_ENDPOINT: &str = "https://validator.nymtech.net";
 pub(crate) const DEFAULT_METRICS_SERVER: &str = "https://metrics.nymtech.net";
 
 // 'DEBUG'
@@ -396,7 +396,7 @@ pub struct MixNode {
     public_sphinx_key_file: PathBuf,
 
     /// Validator server to which the node will be reporting their presence data.
-    #[serde(alias = "presence_directory_server")]
+    #[serde(default = "missing_string_value")]
     validator_rest_url: String,
 
     /// Metrics server to which the node will be reporting their metrics data.