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updatedAt: 2026-05-07T19:36:26.000Z
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# Configure clients before AD Bridge agent installation | AD Bridge

Before you install the AD Bridge agent, configure client computers as indicated in the following sections.

## Configure nsswitch.conf

Before you attempt to join an Active Directory domain, make sure the **/etc/nsswitch.conf** file contains the following line:

```
hosts: files dns
```

The **hosts** line can contain additional information, but it must include the **dns** entry, and we recommend that the **dns** entry appear after the **files** entry.

Computers running Solaris, in particular, may not contain this line in **nsswitch.conf** until you add it.

When you use AD Bridge with Multicast DNS 4 (mDNS4) and have a domain in your environment that ends in **.local**, you must place the **dns** entry before the **mdns4\_minimal** entry and before the **mdns4** entry:

```
hosts: files dns mdns4_minimal [NOTFOUND=return] mdns4
```

The default setting for many Linux systems is to list the **mdns4** entries before the **dns** entry, a configuration that leaves AD Bridge unable to find the domain.

For AD Bridge to work correctly, the **nsswitch.conf** file must be readable by user, group, and world.

> ℹ️
>
> For more information on configuring nsswitch, see the man page for **nsswitch.conf**.

### Configure netsvc.conf on AIX

On AIX computers, ensure the **netsvc.conf** file contains the following line:

```
hosts = local,bind
```

### Restart services

After you update **nsswitch.conf** (or **netsvc.conf**), you must restart the AD Bridge input-output service (**lwio**).

Run the following command as root to restart both services:

```
/opt/pbis/bin/lwsm restart lwio
```

## Configure resolv.conf

Before you attempt to join an Active Directory domain, make sure that **/etc/resolv.conf** on your Linux or Unix client includes a DNS server that can resolve SRV records for your domain.

> ✅ **Example**
>
> `[root@rhel5d Desktop]# cat /etc/resolv.confsearch example.comnameserver 192.168.100.132`

> ℹ️
>
> For more information on **resolv.conf**, see your operating system's man page.

## Configure firewall ports

If you use local firewall settings, such as **iptables**, on a computer running the AD Bridge agent, ensure the following ports are open for outbound traffic.

> ℹ️
>
> The AD Bridge agent is a client. It does not listen on any ports.

| Port | Protocol | Use                                                                                            |
| ---- | -------- | ---------------------------------------------------------------------------------------------- |
| 53   | UDP/ TCP | DNS                                                                                            |
| 88   | UDP/TCP  | Kerberos 5                                                                                     |
| 123  | UDP      | NTP                                                                                            |
| 389  | UDP/TCP  | LDAP                                                                                           |
| 443  | TCP      | AD Bridge Reporting to BeyondInsight                                                           |
| 445  | TCP      | SMB over TCP                                                                                   |
| 464  | UDP/TCP  | Computer password changes (typically after 30 days)                                            |
| 1433 | TCP      | Connection to SQL Server. Open the port you are using. <br />The default port for SQL is 1433. |
| 3268 | TCP      | Global Catalog search                                                                          |

> ℹ️
>
> To view the firewall rules on a Linux computer using **iptables**, execute the following command:

```
iptables - nL
```

## Extend partition size (IBM AIX)

On AIX, you may need to extend the size of certain partitions to complete the installation.

To change the partition size using IBM'S **chfs** command, use **chfs -a size=+200M /opt**.

The example command increases the size of the **opt** partition by 200MB, which is expected to be sufficient for a successful installation.

## Increase max user name length (IBM AIX)

By default, IBM AIX is not configured to support long user and group names, which might present a conflict when you try to log on with a long Active Directory username.

On AIX, group names are truncated when enumerated through the **groups** command.

To increase the max user name length on AIX, use the following syntax:

```
# chdev -l sys0 -a max_logname=MaxUserNameLength+1
```

> ✅ **Example**
>
> `# chdev -l sys0 -a max_logname=255`

This command allocates 254 characters for the user and 1 for the terminating null.

The safest value that you can set **max\_logname** to is **255**.

You must reboot for the changes to take effect:

```
# shutdown -Fr
```