Slow SMB performance when GlobalProtect is connected

SMB traffic is going out through GP adapter even though the SMB server is on the local network.

• Palo Alto Firewalls
• Prisma Access
• GlobalProtect (GP) App
• SMB Server

• SMB Multichannel enables file servers to use multiple network connections simultaneously.
• It facilitates aggregation of network bandwidth and network fault tolerance when multiple paths are available between the SMB 3.0 client and the SMB 3.0 server.
• This capability allows server applications to take full advantage of all available network bandwidth and makes them resilient to network failures.
• When SMB Multichannel is enabled, the SMB protocol attempts to send the traffic across all available interfaces (including \GP adapter) which causes the performance issues.

Disable the multichannel on the client or server to resolve the issue using following commands in Windows PowerShell:

1. Disable SMB Multichannel on the server side:

2. Disable SMB Multichannel on the client side:

Deploy SMB Multichannel Microsoft link