RE: Performance issues with File shares

Here's what I would check:

1. Wireshark was suggested, and I would definitely do this, especially to
see the chattiness between your SMB client and server. Do any packets stand
out that aren't part of the normal SMB traffic during the attempted file
transfer?
2. Are you accessing the file share through a permanently mapped drive, or
are you using the temporary "Network Neighborhood/Network" approach in File
Explorer?
3. Are you accessing the share through a hostname or IP address?
4. If you are accessing the share using a hostname, is the hostname fully
qualified? Is there a DNS lookup during the SMB connection/activity?
Sometimes DNS issues can present themselves with symptoms of slow
performance.
5. If a hostname is used, I would check the DNS resolution traffic with
Wireshark to make sure nothing weird is going on.
6. Are the SMB client and server on the same subnet, or do they require a
gateway to talk to each other (different subnets)? If they require a gateway
(router) to talk to each other, have you check to see if that appliance has
any security features enabled that sniff SMB traffic? Perhaps the security
appliance may be flagging traffic to/from the IBM machine.
6. See what the PC in question is doing in the background while trying to
open the file over the share. Performance Monitor can be used to see if any
unusual disk activity is going on, or high CPU usage.

Traditionally, Windows Defender Firewall only restricts Inbound traffic and
allows any Outbound traffic (unless the rules and profiles have been
modified). If the firewall is under the default configuration, you shouldn't
have to modify the rules for any performance gain. That being said, if
Windows Defender Firewall were the issue, you wouldn't be able to access the
file share in the first place.

Hope this helps.

-----------------------------------------
Jacob Banda
-----------------------------------------

date: Tue, 6 Jul 2021 19:55:53 +0000
from: Greg Wilburn <gwilburn@xxxxxxxxxxxxxxxxxxxxxxx>
subject: RE: Performance issues with File shares

For those that suggest the passwords being the same, that's not possible
right now. Here is the "why"...

The minimum password length for our Active Directory is 12.
We are at password level 1 on Power9 (max length is 10).
I have not yet been able to look at the ramifications for going to password
level 3 (longer and case sensitive). We most definitely will be going here
(and synchronizing our passwords).

The other thing that was not running (fully) before is Windows Defender
Firewall.

If I recall correctly the issue from way back, it was some sort of setting
in Windows 7. Something in Networking, etc. that really helped speed things
up. I just can't recall it.

I disabled "File and Printer Sharing for Microsoft Networks" and that seemed
to help a bit.