fix(email): support custom SMTP EHLO domains (#11398)

app/Livewire/Notifications/Email.php

@@ -6,6 +6,7 @@ use App\Livewire\Notifications\Concerns\TogglesNotificationEvents;
 use App\Models\EmailNotificationSettings;
 use App\Models\Team;
 use App\Notifications\Test;
+use App\Rules\ValidHostname;
 use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
 use Illuminate\Support\Facades\RateLimiter;
 use Livewire\Attributes\Locked;
@@ -57,6 +58,9 @@ class Email extends Component
     #[Validate(['nullable', 'numeric'])]
     public ?string $smtpTimeout = null;
 
+    #[Validate(['nullable', 'string'])]
+    public ?string $smtpEhloDomain = null;
+
     #[Validate(['boolean'])]
     public bool $resendEnabled = false;
 
@@ -129,6 +133,7 @@ class Email extends Component
     {
         if ($toModel) {
             $this->validate();
+            $this->validate(['smtpEhloDomain' => ['nullable', 'string', new ValidHostname]]);
             $this->authorize('update', $this->settings);
             $this->settings->smtp_enabled = $this->smtpEnabled;
             $this->settings->smtp_from_address = $this->smtpFromAddress;
@@ -140,6 +145,7 @@ class Email extends Component
             $this->settings->smtp_username = $this->smtpUsername;
             $this->settings->smtp_password = $this->smtpPassword;
             $this->settings->smtp_timeout = $this->smtpTimeout;
+            $this->settings->smtp_ehlo_domain = $this->smtpEhloDomain;
 
             $this->settings->resend_enabled = $this->resendEnabled;
             $this->settings->resend_api_key = $this->resendApiKey;
@@ -175,6 +181,7 @@ class Email extends Component
                 ? $this->settings->smtp_password
                 : null;
             $this->smtpTimeout = $this->settings->smtp_timeout;
+            $this->smtpEhloDomain = $this->settings->smtp_ehlo_domain;
 
             $this->resendEnabled = $this->settings->resend_enabled;
             $this->resendApiKey = auth()->user()->can('update', $this->settings)
@@ -261,6 +268,7 @@ class Email extends Component
                 'smtpUsername' => 'nullable|string',
                 'smtpPassword' => 'nullable|string',
                 'smtpTimeout' => 'nullable|numeric',
+                'smtpEhloDomain' => ['nullable', 'string', new ValidHostname],
             ], [
                 'smtpFromAddress.required' => 'From Address is required.',
                 'smtpFromAddress.email' => 'Please enter a valid email address.',
@@ -284,6 +292,7 @@ class Email extends Component
             $this->settings->smtp_username = $this->smtpUsername;
             $this->settings->smtp_password = $this->smtpPassword;
             $this->settings->smtp_timeout = $this->smtpTimeout;
+            $this->settings->smtp_ehlo_domain = $this->smtpEhloDomain;
 
             $this->settings->save();
             $this->dispatch('success', 'SMTP settings updated.');
@@ -375,6 +384,7 @@ class Email extends Component
         $this->smtpUsername = $settings->smtp_username;
         $this->smtpPassword = $settings->smtp_password;
         $this->smtpTimeout = $settings->smtp_timeout;
+        $this->smtpEhloDomain = $settings->smtp_ehlo_domain;
 
         if ($settings->resend_enabled) {
             $this->resendEnabled = true;

app/Livewire/SettingsEmail.php

@@ -5,6 +5,7 @@ namespace App\Livewire;
 use App\Models\InstanceSettings;
 use App\Models\Team;
 use App\Notifications\TransactionalEmails\Test;
+use App\Rules\ValidHostname;
 use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
 use Illuminate\Support\Facades\RateLimiter;
 use Livewire\Attributes\Locked;
@@ -50,6 +51,9 @@ class SettingsEmail extends Component
     #[Validate(['nullable', 'numeric'])]
     public ?string $smtpTimeout = null;
 
+    #[Validate(['nullable', 'string'])]
+    public ?string $smtpEhloDomain = null;
+
     #[Validate(['boolean'])]
     public bool $resendEnabled = false;
 
@@ -74,6 +78,7 @@ class SettingsEmail extends Component
     {
         if ($toModel) {
             $this->validate();
+            $this->validate(['smtpEhloDomain' => ['nullable', 'string', new ValidHostname]]);
             $this->settings->smtp_enabled = $this->smtpEnabled;
             $this->settings->smtp_host = $this->smtpHost;
             $this->settings->smtp_port = $this->smtpPort;
@@ -81,6 +86,7 @@ class SettingsEmail extends Component
             $this->settings->smtp_username = $this->smtpUsername;
             $this->settings->smtp_password = $this->smtpPassword;
             $this->settings->smtp_timeout = $this->smtpTimeout;
+            $this->settings->smtp_ehlo_domain = $this->smtpEhloDomain;
             $this->settings->smtp_from_address = $this->smtpFromAddress;
             $this->settings->smtp_from_name = $this->smtpFromName;
 
@@ -95,6 +101,7 @@ class SettingsEmail extends Component
             $this->smtpUsername = $this->settings->smtp_username;
             $this->smtpPassword = $this->settings->smtp_password;
             $this->smtpTimeout = $this->settings->smtp_timeout;
+            $this->smtpEhloDomain = $this->settings->smtp_ehlo_domain;
             $this->smtpFromAddress = $this->settings->smtp_from_address;
             $this->smtpFromName = $this->settings->smtp_from_name;
 
@@ -167,6 +174,7 @@ class SettingsEmail extends Component
                 'smtpUsername' => 'nullable|string',
                 'smtpPassword' => 'nullable|string',
                 'smtpTimeout' => 'nullable|numeric',
+                'smtpEhloDomain' => ['nullable', 'string', new ValidHostname],
             ], [
                 'smtpFromAddress.required' => 'From Address is required.',
                 'smtpFromAddress.email' => 'Please enter a valid email address.',
@@ -184,6 +192,7 @@ class SettingsEmail extends Component
             $this->settings->smtp_username = $this->smtpUsername;
             $this->settings->smtp_password = $this->smtpPassword;
             $this->settings->smtp_timeout = $this->smtpTimeout;
+            $this->settings->smtp_ehlo_domain = $this->smtpEhloDomain;
             $this->settings->smtp_from_address = $this->smtpFromAddress;
             $this->settings->smtp_from_name = $this->smtpFromName;
 

app/Models/EmailNotificationSettings.php

@@ -21,6 +21,7 @@ class EmailNotificationSettings extends Model
         'smtp_username',
         'smtp_password',
         'smtp_timeout',
+        'smtp_ehlo_domain',
 
         'resend_enabled',
         'resend_api_key',

app/Models/InstanceSettings.php

@@ -33,6 +33,7 @@ class InstanceSettings extends Model
         'smtp_username',
         'smtp_password',
         'smtp_timeout',
+        'smtp_ehlo_domain',
         'resend_enabled',
         'resend_api_key',
         'is_dns_validation_enabled',

app/Notifications/Channels/EmailChannel.php

@@ -82,7 +82,10 @@ class EmailChannel
                     'html' => (string) $mailMessage->render(),
                 ]);
             } elseif ($isSmtpEnabled) {
-                $transport = SmtpTransportFactory::fromSettings($settings);
+                $transport = SmtpTransportFactory::fromSettings(
+                    $settings,
+                    config('mail.mailers.smtp.local_domain')
+                );
                 $mailer = new Mailer($transport);
 
                 $email = (new Email)

app/Services/ConfigurationRepository.php

@@ -29,6 +29,8 @@ class ConfigurationRepository
 
         if ($settings->smtp_enabled) {
             $mailerOptions = SmtpTransportFactory::mailerOptions($settings);
+            $localDomain = $settings->smtp_ehlo_domain
+                ?? $this->config->get('mail.mailers.smtp.local_domain');
 
             $this->config->set('mail.default', 'smtp');
             $this->applyMailFrom($from);
@@ -41,7 +43,7 @@ class ConfigurationRepository
                 'username' => $settings->smtp_username,
                 'password' => $settings->smtp_password,
                 'timeout' => $settings->smtp_timeout,
-                'local_domain' => null,
+                'local_domain' => $localDomain,
                 'auto_tls' => $mailerOptions['auto_tls'],
             ]);
         }

app/Support/SmtpTransportFactory.php

@@ -7,7 +7,7 @@ use Symfony\Component\Mailer\Transport\Smtp\Stream\SocketStream;
 
 class SmtpTransportFactory
 {
-    public static function fromSettings(object $settings): EsmtpTransport
+    public static function fromSettings(object $settings, ?string $localDomain = null): EsmtpTransport
     {
         $mode = self::encryptionMode($settings);
 
@@ -28,6 +28,11 @@ class SmtpTransportFactory
         $transport->setUsername($settings->smtp_username ?? '');
         $transport->setPassword($settings->smtp_password ?? '');
 
+        $localDomain = $settings->smtp_ehlo_domain ?? $localDomain;
+        if ($localDomain !== null && $localDomain !== '') {
+            $transport->setLocalDomain($localDomain);
+        }
+
         $stream = $transport->getStream();
         if (isset($settings->smtp_timeout) && $stream instanceof SocketStream) {
             $stream->setTimeout((float) $settings->smtp_timeout);

database/migrations/2026_08_19_090916_add_smtp_ehlo_domain_to_email_settings.php

@@ -0,0 +1,36 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::table('instance_settings', function (Blueprint $table) {
+            $table->string('smtp_ehlo_domain')->nullable();
+        });
+
+        Schema::table('email_notification_settings', function (Blueprint $table) {
+            $table->string('smtp_ehlo_domain')->nullable();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('instance_settings', function (Blueprint $table) {
+            $table->dropColumn('smtp_ehlo_domain');
+        });
+
+        Schema::table('email_notification_settings', function (Blueprint $table) {
+            $table->dropColumn('smtp_ehlo_domain');
+        });
+    }
+};

resources/views/livewire/notifications/email.blade.php

@@ -113,6 +113,10 @@
                         @endcan
                         <x-forms.input canGate="update" :canResource="$settings" id="smtpTimeout" type="number"
                             helper="Timeout value for sending emails." label="Timeout" />
+                        <x-forms.input canGate="update" :canResource="$settings" id="smtpEhloDomain"
+                            placeholder="coolify.example.com"
+                            helper="Fully qualified domain sent in the SMTP EHLO command. Uses the system default when empty."
+                            label="EHLO domain" />
                     </div>
                 </x-application.settings-section>
             </div>

resources/views/livewire/settings-email.blade.php

@@ -8,7 +8,7 @@
         {{-- One bar for the whole page. Three stacked bars made Save run
              submitResend(), which required an API key even when Resend was off. --}}
         <x-unsaved-bar action="submit"
-            targets="smtpFromName,smtpFromAddress,smtpHost,smtpPort,smtpEncryption,smtpUsername,smtpPassword,smtpTimeout,resendApiKey" />
+            targets="smtpFromName,smtpFromAddress,smtpHost,smtpPort,smtpEncryption,smtpUsername,smtpPassword,smtpTimeout,smtpEhloDomain,resendApiKey" />
 
         <form wire:submit="submit">
             <x-application.settings-section title="Sender">
@@ -48,6 +48,9 @@
                         autocomplete="new-password" />
                     <x-forms.input id="smtpTimeout" type="number"
                         helper="Maximum delivery time in seconds." label="Timeout" />
+                    <x-forms.input id="smtpEhloDomain" placeholder="coolify.example.com"
+                        helper="Fully qualified domain sent in the SMTP EHLO command. Uses the system default when empty."
+                        label="EHLO domain" />
                 </div>
             </x-application.settings-section>
         </form>

tests/Feature/SettingsEmailSmtpSetupTest.php

@@ -1,5 +1,6 @@
 <?php
 
+use App\Livewire\Notifications\Email as NotificationEmail;
 use App\Livewire\SettingsEmail;
 use App\Models\InstanceSettings;
 use App\Models\Team;
@@ -34,6 +35,7 @@ function smtpSetupPayload(): array
         'smtpHost' => 'smtp.example.com',
         'smtpPort' => '587',
         'smtpEncryption' => 'starttls',
+        'smtpEhloDomain' => 'coolify.example.com',
         'resendEnabled' => false,
         'resendApiKey' => null,
     ];
@@ -56,9 +58,30 @@ test('saving smtp settings does not require a resend api key when resend is disa
 
     expect($settings->smtp_enabled)->toBeTrue()
         ->and($settings->smtp_host)->toBe('smtp.example.com')
+        ->and($settings->smtp_ehlo_domain)->toBe('coolify.example.com')
         ->and($settings->resend_enabled)->toBeFalse();
 });
 
+test('team smtp settings save their own ehlo domain', function () {
+    setupInstanceAdminForEmailSettings();
+    $team = Team::factory()->create();
+    $user = User::factory()->create();
+    $team->members()->attach($user->id, ['role' => 'admin']);
+
+    $this->actingAs($user);
+    session(['currentTeam' => $team]);
+
+    Livewire::test(NotificationEmail::class)
+        ->fill(smtpSetupPayload())
+        ->set('smtpEnabled', true)
+        ->call('submitSmtp')
+        ->assertHasNoErrors()
+        ->assertNotDispatched('error');
+
+    expect($team->emailNotificationSettings->fresh()->smtp_ehlo_domain)
+        ->toBe('coolify.example.com');
+});
+
 test('saving transactional email settings does not require a resend api key when resend is disabled', function () {
     $user = setupInstanceAdminForEmailSettings();
 

tests/Unit/ConfigurationRepositoryMailConfigTest.php

@@ -27,3 +27,29 @@ it('configures the laravel smtp scheme from encryption', function (string $mode,
     'none on port 465' => ['none', 465, 'smtp', null, '0'],
     'tls on a non-465 port' => ['tls', 587, 'smtps', 'tls', ''],
 ]);
+
+it('preserves the configured smtp ehlo domain', function () {
+    $config = new Repository([
+        'mail' => [
+            'mailers' => [
+                'smtp' => ['local_domain' => 'coolify.example.com'],
+            ],
+        ],
+    ]);
+    $repository = new ConfigurationRepository($config);
+
+    $repository->updateMailConfig((object) [
+        'resend_enabled' => false,
+        'smtp_enabled' => true,
+        'smtp_encryption' => 'starttls',
+        'smtp_host' => 'smtp-relay.gmail.com',
+        'smtp_port' => 587,
+        'smtp_username' => null,
+        'smtp_password' => null,
+        'smtp_timeout' => null,
+        'smtp_from_address' => 'from@example.com',
+        'smtp_from_name' => 'Coolify',
+    ]);
+
+    expect($config->get('mail.mailers.smtp.local_domain'))->toBe('coolify.example.com');
+});

tests/Unit/SmtpTransportFactoryTest.php

@@ -86,6 +86,24 @@ it('applies a configured SMTP timeout to the transport stream', function () {
     expect($transport->getStream()->getTimeout())->toBe(15.0);
 });
 
+it('applies the configured ehlo domain to the transport', function () {
+    $transport = SmtpTransportFactory::fromSettings(
+        smtpSettings(['smtp_ehlo_domain' => 'team.example.com']),
+        'instance.example.com'
+    );
+
+    expect($transport->getLocalDomain())->toBe('team.example.com');
+});
+
+it('falls back to the instance ehlo domain for legacy smtp settings', function () {
+    $transport = SmtpTransportFactory::fromSettings(
+        smtpSettings(),
+        'instance.example.com'
+    );
+
+    expect($transport->getLocalDomain())->toBe('instance.example.com');
+});
+
 it('maps none encryption to laravel mailer options that disable auto tls', function () {
     expect(SmtpTransportFactory::mailerOptions(smtpSettings([
         'smtp_encryption' => 'none',