How to configure WFS (Windows File Sharing ) Acceleration and configure file shares on SonicWall WA

03/26/2020 13 13506

DESCRIPTION:
How to configure WFS (Windows File Sharing ) Acceleration and configure file shares on SonicWall WAN Acceleration Appliances & Software

RESOLUTION:

How to configure WFS (Windows File Sharing ) Acceleration on SonicWall WAN Acceleration Appliances and setting up file shares

How to configure WFS (Windows File Sharing ) Acceleration on SonicWall WAN Acceleration Appliances
Consider the following typical deployment scenario where Head Quarters and Remote Office are connected via Site-Site VPN Tunnel.
SonicWall WAN Acceleration devices are directly connected to the managing UTM appliances as shown at each location. At head quarters there
is a Domain Controller, DNS Server and 2 file servers. Remote Office has no local domain controller, DNS server, File Servers. Users at remote
office access the resources at the head quarters via Site-Site VPN.


Assumptions:

There is a Site-Site VPN configured between Head Quarters and Remote Office using IPsec or Route based VPN. Please refer to the WAN
Acceleration deployment modes articles/feature module for details of deployment modes.

Recommendations:

1. Create Static DHCP scope for WXA Appliance on the managing SonicWall UTM Appliance 
2. If the remote offices also have Domain Controllers and DNS servers, it is recommended to use the local DNS server addresses and 
   domain DNS name in the DHCP scope. Configure Domain Name and Domain DNS servers’ addresses in the configured DHCP scope. WXA 
   Appliance auto-discovers Kerberos, LDAP, NTP servers based on this information to assist in joining the Appliance to the domain. 
3. Review the LDAP, Kerberos and NTP services. In a multi-site domain where Sites and Services are not explicitly configured, the WXA 
   might choose servers that are at another remote site instead of at head office. 
4. Though not essential, it is recommended to create Reverse Lookup Zone for the networks on DNS servers for the necessary local and 
   remote networks for WFS to update PTR records. Remote Lookup Zones configuration depends on whether WXA Appliance is using 
   NAT’ed IP (of the Managing UTM Appliance’s one of Interface IP address or other IP address) or using its own IP address (no NAT) 
5. It is recommended that WXA Appliance gets NTP updates from local Domain Controller 
6. It is recommended that the DNS server accepts secure updates 
7. SonicWall Recommends configuring the Zone properties of Interface to which SonicWall WAN Acceleration WXA Appliance is 
   connected as LAN Zone so that the default access rules allow traffic between WXA Appliances at both locations. This simplifies the 
   process of configuration and deployments. 

For example consider Head Quarters, if SonicWall WXA Appliance is deployed in DMZ, then access rules must be configured/updated to allow
traffic from VPN->DMZ, LAN->DMZ so that traffic to WXA Appliance from VPN (includes traffic from remote LAN Zone as well as from WXA
Appliance) and from LAN zone (Traffic from Domain Controllers, DNS Servers, File Servers) is allowed to WXA Appliance. Similarly traffic must be
allowed from DMZ headquarters to VPN remote must be allowed. If additional domain controllers and file servers are located in any other Zone
or custom zone, necessary access rules must be configured to allow traffic from/to WXA Appliance to those Zones as well. Similar configuration
must be followed at the remote location. Custom Access rules depend on specifics of deployment scenarios.

The following services are being used by WAN Acceleration and Client PCs for Domain Controller, DNS Server, NTP server, File Server Services.

Client PCs require AD Server Services (TCP 135, 137, 139, 445) for file services and require AD Directory Services for Domain Services. WXA
Appliances also require these services for Domain Services and file shares proxy.

Steps involved:

1. Pre-requisites
2. Enabling WFS acceleration and using correct IP address for WXA to use in NAT translation.
3. Joining WXA devices to the domain
4. Setting up shares
5. Testing shares
 

Pre-requisites:

1. Site-Site VPN policy is already configured between Head Quarters and remote site to allow traffic between the networks. It is not
required to include WXA Subnets in the VPN Policy/Networks.

2. WXA Appliance at both locations are connected to their respective Interfaces/Zones and provisioned with IP address, Domain Name
and Domain DNS Servers and NTP server. It is essential that WXA Appliances are configured to automatically get Domain DNS server
and Domain Name information from the DHCP scope created for WXA Appliance. If the remote offices also have Domain Controllers
and DNS servers, it is recommended to use the local DNS server addresses in the DHCP scope.

Enabling WFS acceleration and using correct IP address for WXA to use in NAT translation:

As mentioned in pre-requisite # 1, it is not required to include WXA Subnets in the VPN Policy/Networks. By default WXA Appliances uses NAT’ed 
IP of X0 interface IP address of Managing UTM Appliance for communications and it is essential that the NAT’ed IP be a part of VPN networks. 
For example, WXA 4000 that is deployed at headquarters gets NAT’ed to X.X.1.10 and WXA 2000 at remote gets NAT’ed to A.A.240.1. WXA 
Appliances at both the locations use these NAT’ed IP addresses for communication and hence eliminate the necessity to include WXA subnets as 
a part of VPN Networks. For NAT’ed IP address, it can be Managing UTM appliance’s interface IP address or any IP address that is not used by 
any other device. But the IP address being has to be a part of the VPN networks in either case. But for simplicity, you can choose to use 
Managing UTM appliance’s Interface IP address so that another IP is not needed. 

NAT policies that are essential are automatically created based on the NAT’ed IP address being used as shown below.

On the managing SonicWall UTM appliance, navigate to WAN Acceleration->WFS Acceleration and enable WFS Acceleration.

Joining WXA Appliances to the domain:

Once WXA Appliances are configured properly with DHCP scope, based on the Domain Name and configured DNS servers, WXA Appliances
automatically discovers FQDN of the domain, NetBIOS name, Kerberos, LDAP, Time Server. If any of them are not discovered properly, then that
entry can be manually edited. For example, in this case, NetBIOS name is not correctly identified and is discovered as UTM and needs manual
editing.

Host name can be edited or changed as per requirement.

Once all the necessary edits are done, click on “Join Domain” to add WXA Appliance to the domain using the domain account that has
permissions to join to the domain.

WXA at Head Quarters added to the domain.

Follow the same steps to add WXA2000 at remote office to the domain.

Once both WXA Appliances are added to the domain, corresponding Computer Accounts for WXA Appliances, DNS Host name and PTR
records are automatically created on Domain Controller and DNS servers as shown. For PRT records to get updated, relevant Reverse Lookup
Zones must be configured on the DNS servers. Networks used for reverse lookup Zones depend on whether WFS acceleration is using NAT or
no NAT. In this deployment, WXA uses NAT’ed IP for WFS Services and only the X0 Subnets are used as Networks in Reverse Lookup Zones. If
WXA Appliances are not using NAT, then reverse Look up Zone networks must also be configured for WXA Subnets at both locations.

Adding File Shares:

Adding Shares that are hosted on 2 file servers at head quarters.

• Adding /Configuring Shares that are hosted on 1st File Server

o Configuration on HQ WXA Appliance
o Configuration on Remote WXA Appliance

• Adding/Configuring Shares that are hosted on 2nd File Server

o Creating Service Principle Names (SPNs) for mapping shares. More on SPNs creation is discussed below.
o Configuration on HQ WXA Appliance
o Configuration on Remote WXA Appliance

1. Adding Shares that are hosted on 1st File Server:

To add shares, you can choose to add all available shares or choose specific shares. For adding shares on the first file server, you can use
WXA-4000 as Hostname for Head Quarters WXA Appliance and WXA-2000 as hostname for remote WXA Appliance.

Adding 2nd and subsequent shares that are hosted on different file servers requires creation of Service Principle Names (SPN) on Active
Directory.

Configuring 1st File Server shares on Head Quarters WXA-4000
Navigate to WAN Acceleration-> WFS Acceleration->Shares and add shares. In this deployment, as the File Servers are located at Head
Quarters, WXA Appliance at Head Quarters directly access these file servers. So on head Quarters WXA Appliance, Remote Server name
points to the actual File Server and the Local Server name is the WXA Appliance at head quarters.

Configuring 1st File Server shares on Remote WXA-2000

Navigate to WAN Acceleration-> WFS Acceleration->Shares and add shares. In this deployment, as the file servers are located at Head
Quarters, remote WXA Appliance accesses these shares via WXA Appliance at Head Quarters. So on remote office WXA Appliance,
Remote Server name points to the Head Quarters WXA-4000 and the Local Server name is the WXA Appliance at remote office.

2. Adding Shares that are hosted on 2nd File Server:
Adding 2nd and subsequent shares that are hosted on different file servers requires creation of Service Principle Names (SPN) on Active
Directory. These SPNs are used as CIFS service names when mapping and accessing File Server shares. 
Creation of SPNs shown below is used for demonstration purposes only and additional references and knowledge of customer is
required while creating/modifying/deleting SPN entries on Domain Controllers.

Create Service Principle Names for head Quarters and Remote Office WXA Appliances for CIFS/SMB Traffic

For setting up file shares that are hosted on 2nd File Server, WXA-4000-GMS is used as Hostname for Head Quarters WXA and WXA-2000-
GMS is used as Hostname for remote Office WXA

Configuring 2nd File Server shares on Head Quarters WXA-4000

Navigate to WAN Acceleration-> WFS Acceleration->Shares and add shares. In this deployment, as the File Servers are located at Head
Quarters, WXA Appliance at Head Quarters directly access these file servers. So on head Quarters WXA Appliance, Remote Server name
points to the actual File Server and the Local Server name is the WXA Appliance at head quarters.
On head Quarters WXA Appliance, Remote Server name points to the actual File Server (2nd File Server) and the Local Server name is the
SPN name created for WXA Appliance at head quarters – (WXA-4000-GMS)

Configuring 2nd File Server shares on WXA-2000

Navigate to WAN Acceleration-> WFS Acceleration->Shares and add shares. In this deployment, as the file servers are located at Head
Quarters, remote WXA Appliance accesses these shares via WXA Appliance at Head Quarters. So on remote office WXA Appliance,
Remote Server name points to the Head Quarters WXA-4000 and the Local Server name is the WXA Appliance at remote office.
On remote office WXA Appliance, Remote Server name points to the Head Quarters WXA-4000-GMS (newly created SPN) and the Local
Server name is the WXA Appliance newly created SPN at remote office – (WXA-2000-GMS)

Once the shares are configured for 2nd File Server, WXA Appliances updates A record and the associated PTR record for newly created
SPNs (depending on Reverse Lookup Zone) on DNS server using the NAT’ed IP. If for some reason the creation on A record and PTR
doesn’t succeed, domain Admin can manually add them as shown below.

Manually adding SPN hostnames in DNS

Create new Host (A) records in DNS for the newly created SPNs as shown below and appropriately choose the option to update
corresponding PTR record as well.

The newly created Hostname for Head Quarters WXA should be updated with the NAT’ed IP of X0 Interface of head Quarters UTM
Appliance and newly created Hostname for remote office WXA should be updated with the NAT’ed IP of X0 Interface of remote office
UTM Appliance as shown below



Once these A record and PTR record are created for Head Quarters and Remote Office WXA Appliances, you can ping them using these
hostnames which resolves to NAT’ed IPs of Xo interfaces at Head Quarters and Remote Offices UTM Appliances.

Now WXA-4000 and WXA-4000-GMS should resolve to X.X.1.100 and WXA-2000 and WXA-2000-GMS should resolve to A.A.240.1

Testing:

All shares should be identical whether accessed using shares using real File Sever, or shares using Head Quarters WXA Share name or
Remote Office Share Name.

In this case, Remote Office users should use \WXA-2000 and \WXA-2000-GMS as share names to access resources on the Head
Quarters that are actually hosted on File Server 1 and File Server 2. Head office users must access the shares using the Real Server as the
actual servers are local in this case.

Network administrators must also map the real shares mapped to the real server for redundancy in case of WXA appliance at remote
office goes down.


Tools available for testing and troubleshooting: