Frequent disconnection, after getting new router

[999null 0]

HI,

I am experiencing Frequent disconnection and reconnection, after my isp installed a new router. 

I suspect it's because of my ISP dns. (I have not changed it to cloudflare or quad9 yet which I had before). Could this be issue?

It's on both of my ubuntu servers (2 old Laptops one connected via ethernet, another is via wifi ). They worked perfectly, and were connected for weeks. 

Is there any way to drill down where the disconnection occurs? Is it on my server end? my router? or airvpn end?

I also have ipv6 disabled and  some other settings -- 

# Some network settings
net.ipv4.tcp_fin_timeout = 20
net.ipv4.tcp_slow_start_after_idle = 0
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_fastopen=3
net.ipv4.tcp_congestion_control=bbr
#####
net.core.rmem_max = 16777216
# Maximum Socket Send Buffer. 16MB per socket - which sounds like a lot, but will virtually never consume that much. Default: 212992
net.core.wmem_max = 16777216
# Increase the write-buffer-space allocatable: min 4KB, def 12MB, max 16MB. Default: 4096 16384 4194304
net.ipv4.tcp_wmem = 4096 12582912 16777216
# Increase the read-buffer-space allocatable: min 4KB, def 12MB, max 16MB. Default: 4096 16384 4194304
net.ipv4.tcp_rmem = 4096 12582912 16777216

# Tells the system whether it should start at the default window size only for new TCP connections or also for existing TCP connections that have been idle for too long. Default: 1
##net.ipv4.tcp_slow_start_after_idle = 0
# Allow reuse of sockets in TIME_WAIT state for new connections only when it is safe from the network stack’s perspective. Default: 0
##net.ipv4.tcp_tw_reuse = 1
# Do not last the complete time_wait cycle. Default: 0
# only works from Linux 2.4 to 4.11
net.ipv4.tcp_tw_recycle = 1
# Minimum time a socket will stay in TIME_WAIT state (unusable after being used once). Default: 60
net.ipv4.tcp_fin_timeout = 30
net.ipv6.conf.all.disable_ipv6=1
net.ipv6.conf.default.disable_ipv6=1
net.ipv6.conf.lo.disable_ipv6=1

 

Quote

(connected via wireguard with persist alive set to 15)

 

[Interface]
Address = xxxxx/10
PrivateKey = xxx=
DNS = 10.128.0.1

[Peer]
PublicKey = x+xxxx=
PresharedKey = xx/xx/xx=
Endpoint = xxxxx:1637
AllowedIPs = 0.0.0.0/0
PersistentKeepalive = 15

[OpenSourcerer 1359]

You didn't post any logs, so not sure what's triggering the disconnect.

Please don't set all these weird network settings and try again. I mean, do you even know the difference between cubic and bbr congestion control algorithms? Can you explain congestion control to begin with?
 

7 hours ago, 999null said:

# only works from Linux 2.4 to 4.11

This is a particularly interesting line indicating you copied those settings from somewhere. You normally know which Linux kernel you're running on and can decide whether this option should be there or not (or at least commented out).
 

7 hours ago, 999null said:

or airvpn end?

We can safely assume that it's not, otherwise the forums would be swarmed with "I have the same issue" posts.

[999null 0]

13 hours ago, OpenSourcerer said:

You didn't post any logs, so not sure what's triggering the disconnect

How to view these logs? where are they located? (ubuntu 20.04)

[OpenSourcerer 1359]

Using Wireguard, the logs should be in the journal.

# journalctl -k --grep wireguard

.

[999null 0]

https://ibb.co/XWHS8NH

Turns out there is a setting on my router for "some" devices. I turned it on, and my connections seem to stay stabilize my connection. 

"Always Broadcast DHCP Server"

I also added my laptops LAN addresses in QoS setting, to give it a higher priority.
 

[OpenSourcerer 1359]

6 hours ago, 999null said:

I also added my laptops LAN addresses in QoS setting, to give it a higher priority.

I think that one is the real MVP. Can't imagine the DHCP thing to be of help, unless it's not the VPN connection breaking but the physical one to your router.