Intervlan forwarding delay? Slow SSH/https across vlans

RouterOS Beginner Basics
1

Hi There!

I recently got an rb4011 to use as my edge and have gotten almost everything working as I would like it, but cannot seem to figure out this one particular issue. Honestly I am not sure if this is more of a proxmox issue or if it is a networking issue, but the issue presented itself when switching over to using Mikrotik for the edge instead of the Ubiquiti edgerouter :frowning:

Vlan 11 - Lab LAN
Vlan 21 - Home LAN

I am doing this from the frame of reference of being on the Home LAN.

The proxmox hypervisor bridge has interfaces on both the Home LAN and the Lab LAN, and if I SSH the IP of the interface on the same network there isn’t a delay.When trying to ssh from my Home LAN to one of my proxmox hypervisors bridge interface on the Lab LAN, there is a 10-15 second delay before it responds. What makes things weird is that there doesn’t seem to be a delay when SSHing to a VM on that same example hypervisor whos interface is also on that bridge, which leads me to believe this is somehow a proxmox issue. I am just hoping someone has some familiarity that can set me straight.

An example of the network interface on one of the proxmox hosts:
auto vmbr2
iface vmbr2 inet static
address 192.168.0.44/24
bridge-ports eno1
bridge-stp off
brdige-fd 0
bridge-vlan-aware yes
bridge-vids 2-4094

auto vmbr2.11
iface vmbr2.11 inet static
address 10.1.0.4/24
gateway 10.1.0.1

auto vmbr2.21
iface vmbr2.21 inet static
address 192.168.1.35/24

I don’t know what configs on my rb4011 would be relevant to this as I’m not sure if this is a layer 2 issue or if this has something to do with the default fasttrack rules. Any help would be appreciated and any information I can provide will be done.

2

First thing that comes to mind is the typical reverse DNS query most linux distros do when accessed via SSH. If it cannot reverse-query the source IP, you may experience this delay.

Posting the 4011 config will definitely help.

3

.

First thing that comes to mind is the typical reverse DNS query most linux distros do when accessed via SSH

.
agreed by the 100%
.
check /etc/ssh/sshd_config of your containers …vm’s whatsoever …
.

#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3

PermitRootLogin vielleicht
##############
UseDNS no
##############
#PidFile /var/run/sshd.pid
#MaxStartups 10:30:100
#PermitTunnel no
#ChrootDirectory none

.
or even better; setup full-functional dns (including reverse-dns) for your entire network ..
.

4

You guys hit the nail on the head, my Powerdns recursor wasn’t forwarding the reverse dns lookups!!! I’ve been trying to figure this out for like a week!