Monthly Archives: August 2019

Demystifying SMB 3 x multichannel – part 9 – VM1 (Debian Linux 10) on Host1 to VM2 (Windows Server 2019) on Host2

I finally managed to make it work … 🙂 So this time we are trying to establish multichannel between Debian Linux with Samba 4.9.5-Debian and Windows server 2019 (that preferres SMB 3.1.1 dialect). Each of VMs on separate Hyper-V hosts has 4 virtual network adapters connected. I entered the hostnames of VMs in hosts files both – on Windows and Linux as I am not running any DNS server in the test network.
So I added 4 entries on each machine. On Debian I have created a simple smb.conf example file to make it work:

[global]
workgroup = WORKGROUP
interfaces = eth0, eth1, eth2, eth3
bind interfaces only = Yes
vfs objects = recycle aio_pthread
aio read size = 1
aio write size = 1
strict locking = No
use sendfile = no
server multi channel support = yes
server string = samba server
security = USER
encrypt passwords = yes
smb passwd file = /etc/samba/smbpasswd
guest ok = yes

[storage]
comment = Storage
path = /var/samba
writeable = yes
public = no

As you can see in video by using Linux command in terminal: smbstatus I am getting similar information as running get-smbmultichannel Powershell cmdlet on Windows. I can clearly see how servers are connected between them by using SMB protocol.

As you can see in video Windows machine, from which I am copying data to Linux utilizes all four network adapters but we are getting only 2 gigabit throughput. On Linux side there are only two NICs utilized. I was not able to make it work by using all four adapters (like machines were utilizing in previous part in Windows VM to Windows VM scenario). Well I just wanted to demonstrate that concept works also in mixed environment with Windows and Linux.

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(Mass) Modifying SOA record values by using Set-DnsServerResourceRecord

Today I wanted to update all serial numbers (to make sure that are written in YYYYMMDD00 way) on my primary DNS zones on my Windows server 2019 DNS server.

This is the script to do this massive change – by using this script anyone can modify any parameters in DNS.

$allzones = Get-DnsServerZone | Where-Object -Property ZoneType -EQ -Value “Primary”
foreach ($allzone in $allzones) {
$old = “”
$new = “”
$old = Get-DnsServerResourceRecord -ZoneName $allzone.ZoneName -Name “@” -RRType Soa
$new = $old.Clone()
$new.RecordData.SerialNumber = 2019080400
Set-DnsServerResourceRecord -OldInputObject $old -NewInputObject $new -ZoneName $allzone.ZoneName -PassThru
}