diff --git a/releasenotes/notes/add-image-alt-ssh-user-config-option-1b775af2f468aa5b.yaml b/releasenotes/notes/add-image-alt-ssh-user-config-option-1b775af2f468aa5b.yaml
new file mode 100644
index 0000000..159bbe8
--- /dev/null
+++ b/releasenotes/notes/add-image-alt-ssh-user-config-option-1b775af2f468aa5b.yaml
@@ -0,0 +1,10 @@
+---
+features:
+  - A new config option in the validation section, image_alt_ssh_user,
+    to specify the user name used to authenticate to an alternative
+    instance (instance using image_ref_alt) in tests. By default this
+    is set to root.
+  - A new config option in the validation section, image_alt_ssh_password,
+    to specify the password used to authenticate to an alternative
+    instance (instance using image_ref_alt) in tests. By default this
+    is set to password.
diff --git a/tempest/api/compute/base.py b/tempest/api/compute/base.py
index 8b847fc..d19b4cd 100644
--- a/tempest/api/compute/base.py
+++ b/tempest/api/compute/base.py
@@ -171,8 +171,11 @@
         cls.flavor_ref = CONF.compute.flavor_ref
         cls.flavor_ref_alt = CONF.compute.flavor_ref_alt
         cls.ssh_user = CONF.validation.image_ssh_user
+        cls.ssh_alt_user = CONF.validation.image_alt_ssh_user
         cls.image_ssh_user = CONF.validation.image_ssh_user
+        cls.image_alt_ssh_user = CONF.validation.image_alt_ssh_user
         cls.image_ssh_password = CONF.validation.image_ssh_password
+        cls.image_alt_ssh_password = CONF.validation.image_alt_ssh_password
 
     @classmethod
     def is_requested_microversion_compatible(cls, max_version):
diff --git a/tempest/api/compute/servers/test_server_actions.py b/tempest/api/compute/servers/test_server_actions.py
index 343d3ee..4527aa9 100644
--- a/tempest/api/compute/servers/test_server_actions.py
+++ b/tempest/api/compute/servers/test_server_actions.py
@@ -228,7 +228,7 @@
             # 4.Plain username/password auth, if a password was given.
             linux_client = remote_client.RemoteClient(
                 self.get_server_ip(rebuilt_server, validation_resources),
-                self.ssh_user,
+                self.ssh_alt_user,
                 password,
                 validation_resources['keypair']['private_key'],
                 server=rebuilt_server,
@@ -310,7 +310,7 @@
                 self.os_primary)
             linux_client = remote_client.RemoteClient(
                 self.get_server_ip(server, validation_resources),
-                self.ssh_user,
+                self.ssh_alt_user,
                 password=None,
                 pkey=validation_resources['keypair']['private_key'],
                 server=server,
diff --git a/tempest/config.py b/tempest/config.py
index 28a70c2..26a7fab 100644
--- a/tempest/config.py
+++ b/tempest/config.py
@@ -865,10 +865,17 @@
     cfg.StrOpt('image_ssh_user',
                default="root",
                help="User name used to authenticate to an instance."),
+    cfg.StrOpt('image_alt_ssh_user',
+               default="root",
+               help="User name used to authenticate to an alt instance."),
     cfg.StrOpt('image_ssh_password',
                default="password",
                help="Password used to authenticate to an instance.",
                secret=True),
+    cfg.StrOpt('image_alt_ssh_password',
+               default="password",
+               help="Password used to authenticate to an alt instance.",
+               secret=True),
     cfg.StrOpt('ssh_shell_prologue',
                default="set -eu -o pipefail; PATH=$$PATH:/sbin:/usr/sbin;",
                help="Shell fragments to use before executing a command "
diff --git a/tempest/scenario/test_network_advanced_server_ops.py b/tempest/scenario/test_network_advanced_server_ops.py
index e26dc9d..dbab212 100644
--- a/tempest/scenario/test_network_advanced_server_ops.py
+++ b/tempest/scenario/test_network_advanced_server_ops.py
@@ -80,8 +80,8 @@
         return floating_ip
 
     def _check_network_connectivity(self, server, keypair, floating_ip,
-                                    should_connect=True):
-        username = CONF.validation.image_ssh_user
+                                    should_connect=True,
+                                    username=CONF.validation.image_ssh_user):
         private_key = keypair['private_key']
         self.check_tenant_network_connectivity(
             server, username, private_key,
@@ -95,12 +95,13 @@
                                    'Public network connectivity check failed',
                                    server)
 
-    def _wait_server_status_and_check_network_connectivity(self, server,
-                                                           keypair,
-                                                           floating_ip):
+    def _wait_server_status_and_check_network_connectivity(
+        self, server, keypair, floating_ip,
+        username=CONF.validation.image_ssh_user):
         waiters.wait_for_server_status(self.servers_client, server['id'],
                                        'ACTIVE')
-        self._check_network_connectivity(server, keypair, floating_ip)
+        self._check_network_connectivity(server, keypair, floating_ip,
+                                         username=username)
 
     @decorators.idempotent_id('61f1aa9a-1573-410e-9054-afa557cab021')
     @decorators.attr(type='slow')
@@ -137,10 +138,11 @@
         server = self._setup_server(keypair)
         floating_ip = self._setup_network(server, keypair)
         image_ref_alt = CONF.compute.image_ref_alt
+        username_alt = CONF.validation.image_alt_ssh_user
         self.servers_client.rebuild_server(server['id'],
                                            image_ref=image_ref_alt)
         self._wait_server_status_and_check_network_connectivity(
-            server, keypair, floating_ip)
+            server, keypair, floating_ip, username_alt)
 
     @decorators.idempotent_id('2b2642db-6568-4b35-b812-eceed3fa20ce')
     @testtools.skipUnless(CONF.compute_feature_enabled.pause,