diff --git a/server/src/uds/core/util/validators.py b/server/src/uds/core/util/validators.py
index 4649785ba..5a2028289 100644
--- a/server/src/uds/core/util/validators.py
+++ b/server/src/uds/core/util/validators.py
@@ -263,7 +263,7 @@ def validate_host_port(host_port_pair: str, field_name: typing.Optional[str] = N
             dj_validators.validate_ipv46_address(host)
             return host, validate_port(port)
         except Exception:
-            return validate_hostname(host, 255, False), validate_port(port)
+            return validate_hostname(host, 255, True), validate_port(port)
     except Exception:
         raise exceptions.ui.ValidationError(_('{} is not a valid host:port pair').format(host_port_pair + field_name)) from None
 
diff --git a/server/src/uds/services/Proxmox/proxmox/client.py b/server/src/uds/services/Proxmox/proxmox/client.py
index 653935e0c..cc40a1f83 100644
--- a/server/src/uds/services/Proxmox/proxmox/client.py
+++ b/server/src/uds/services/Proxmox/proxmox/client.py
@@ -670,25 +670,29 @@ class ProxmoxClient:
     def set_vm_net_mac(
         self,
         vmid: int,
-        mac: str,
-        netid: typing.Optional[str] = None,
+        macaddr: str,
+        netid: typing.Optional[str] = None,  # net0, net1, ...
         node: typing.Optional[str] = None,
     ) -> None:
         node = node or self.get_vm_info(vmid).node
-        # First, read current configuration and extract network configuration
-        config = self.do_get(f'nodes/{node}/qemu/{vmid}/config', node=node)['data']
-        if netid not in config:
-            # Get first network interface (netX where X is a number)
-            netid = next((k for k in config if k.startswith('net') and k[3:].isdigit()), None)
-        if not netid:
-            raise exceptions.ProxmoxError('No network interface found')
+    
+        net: types.NetworkConfiguration = types.NetworkConfiguration.null()
+        
+        cfg = self.get_vm_config(vmid, node)
+        
+        if netid is None:
+            net = cfg.networks[0]
+        else:
+            for i in cfg.networks:
+                if i.net == netid:
+                    net = i
+                    break
+                
+        # net should be the reference to the network we want to update
+        if net.is_null():
+            raise exceptions.ProxmoxError(f'Network {netid} not found for VM {vmid}')
 
-        netdata = config[netid]
-
-        # Update mac address, that is the first field <model>=<mac>,<other options>
-        netdata = re.sub(r'^([^=]+)=([^,]+),', r'\1={},'.format(mac), netdata)
-
-        logger.debug('Updating mac address for VM %s: %s=%s', vmid, netid, netdata)
+        logger.debug('Updating mac address for VM %s: %s=%s', vmid, netid, net.macaddr)
 
         self.do_post(
             f'nodes/{node}/qemu/{vmid}/config',
diff --git a/server/src/uds/services/Proxmox/proxmox/types.py b/server/src/uds/services/Proxmox/proxmox/types.py
index 3878c4c65..0346609be 100644
--- a/server/src/uds/services/Proxmox/proxmox/types.py
+++ b/server/src/uds/services/Proxmox/proxmox/types.py
@@ -221,17 +221,30 @@ class TaskStatus:
 class NetworkConfiguration:
     net: str
     type: str
-    mac: str
+    macaddr: str
+
+    netdata: str  # Original data
+    
+    def is_null(self) -> bool:
+        return self.net == ''
+
+    def set_mac_address(self, macaddr: str) -> None:
+        self.macaddr = macaddr
+        # Replace mac address in netdata
+        self.netdata = re.sub(r'^([^=]+)=([^,]+),', r'\1={},'.format(macaddr), self.netdata)
 
     @staticmethod
-    def from_str(net: str, value: str) -> 'NetworkConfiguration':
-        v = NETWORK_RE.match(value)
+    def from_str(net: str, netdata: str) -> 'NetworkConfiguration':
+        v = NETWORK_RE.match(netdata)
         type = mac = ''
         if v:
             type, mac = v.group(1), v.group(2)
 
-        return NetworkConfiguration(net=net, type=type, mac=mac)
+        return NetworkConfiguration(net=net, type=type, macaddr=mac, netdata=netdata)
 
+    @staticmethod
+    def null() -> 'NetworkConfiguration':
+        return NetworkConfiguration(net='', type='', macaddr='', netdata='')
 
 @dataclasses.dataclass
 class HAInfo:
diff --git a/server/src/uds/services/Proxmox/service_fixed.py b/server/src/uds/services/Proxmox/service_fixed.py
index d4da105cf..b7a2d49c3 100644
--- a/server/src/uds/services/Proxmox/service_fixed.py
+++ b/server/src/uds/services/Proxmox/service_fixed.py
@@ -213,7 +213,7 @@ class ProxmoxServiceFixed(FixedService):  # pylint: disable=too-many-public-meth
 
     def get_mac(self, vmid: str) -> str:
         config = self.provider().api.get_vm_config(int(vmid))
-        return config.networks[0].mac.lower()
+        return config.networks[0].macaddr.lower()
 
     def get_ip(self, vmid: str) -> str:
         return self.provider().api.get_guest_ip_address(int(vmid))
diff --git a/server/src/uds/services/Proxmox/service_linked.py b/server/src/uds/services/Proxmox/service_linked.py
index 9af28651c..6479bac7c 100644
--- a/server/src/uds/services/Proxmox/service_linked.py
+++ b/server/src/uds/services/Proxmox/service_linked.py
@@ -265,7 +265,7 @@ class ProxmoxServiceLinked(DynamicService):
         # If vmid is empty, we are requesting a new mac
         if not vmid:
             return self.mac_generator().get(self.get_macs_range())
-        return self.provider().api.get_vm_config(int(vmid)).networks[0].mac.lower()
+        return self.provider().api.get_vm_config(int(vmid)).networks[0].macaddr.lower()
 
     def start(self, caller_instance: typing.Optional['DynamicUserService | DynamicPublication'], vmid: str) -> None:
         if isinstance(caller_instance, ProxmoxUserserviceLinked):