TAILMON TAILMON v1.3.0 -Aug 24, 2025- WireGuard-based Tailscale Installer, Configurator and Monitor (Available in AMTM!)

[jksmurf]

I don't use TAILMON but it looks like you would add it to your custom command line (4):

CMD="--advertise-routes=192.168.9.0/24,192.168.53.15/32 --accept-dns=false"

Yep, seems to have done the trick!

No endless loops, I can see the names in /et/resolv.conf

nameserver 1.1.1.1
nameserver 1.0.0.1
nameserver 2606:4700:4700::1111
nameserver 2606:4700:4700::1001

Thanks as always @ColinTaylor

[EDIT2] Acknowledging I am also trying an unstable track version due to this development (but now reveretd to stable), it seems not to be able to reach the DNS servers in any case, but only the local one.

# Health check:
#     - This is an unstable version of Tailscale meant for testing and development purposes. Please report any issues to Tailscale.
#     - Tailscale can't reach the configured DNS servers. Internet connectivity may be affected.

Tailscale Service Options (Custom Mode)
PRECMD: modprobe tun
ARGS: --state=/opt/var/tailscaled.state --statedir=/opt/var/lib/tailscale
PREARGS: nohup

Tailscale Connection Commandline
--advertise-routes=192.168.9.0/24,192.168.53.15/32 --accept-dns=false

  21s / 35% [e=Exit] [Selection?  ]

# Health check:
#     - This is an unstable version of Tailscale meant for testing and development purposes. Please report any issues to Tailscale.

Tailscale Service Options (Custom Mode)                                                                                                     
PRECMD: modprobe tun
ARGS: --state=/opt/var/tailscaled.state --statedir=/opt/var/lib/tailscale
PREARGS: nohup

Tailscale Connection Commandline                                                                                                           
--advertise-routes=192.168.47.0/24 --accept-dns=false

  17s / 28% [e=Exit] [Selection?  ]

[EDIT2] So I can (from my Phone (LTE)) get to the one that does not have the error message. The local one, not. Investigating...

So I thought I "fixed" the local error by selecting Enable under IPv6 "Connect to DNS Server automatically" (which meant giving up my Cloudflare IPv6 DNS) but the error came back; so not a fix.

 

[jksmurf]

Hi Viktor,

Odd thing happening here, I cannot seem to update to the Tailscale Beta (anymore I think, life's a blur atm).
IIRC I updated it yesterday to whatever the latest unstable is, then downgraded it back to 1.88.3 and now I cannot seem to go back up to unstable track again?
I tried starting from within amtm, from the CL (just tailmon), in Monitoring Mode with screen, and without, same result?
It does the whole download install thing but keeps saying 1.88.3 at the end of it, each trial the same.
" Tailscale version" at the CL says 1.88.3.
There is a small discrepancy here "downloaded 30688878, want 30688885" but I am not sure if that is the issue.
I am in CUSTOM Mode btw, if that has aby bearing on it.

How can I get you logs to see what is happening?

Press any key to continue...
  TAILMON Main Setup and Configuration Menu

  Please choose from the various options below, which allow you to perform high level
  actions in the management of the TAILMON script.
 ---------------------------------------------------------------------------------------

  ( 1) : Install Tailscale Entware Package(s)         : Installed
    |--- (R)e-(S)tart / S(T)op Tailscale Service      |--- Started
    |--- (U)p / (D)own Tailscale Connection           |--- Connected
    |--- U(P)date Tailscale Binary to latest version  |--- v1.88.3
    |--- Update Tailscale Binary to latest (B)ETA
    |--- (F)orce Downgrade to Older Tailscale version
    |--- (I)ssue Connection '--reset' Command
  ( 2) : Uninstall Tailscale Entware Package(s)
  ( 3) : Set Tailscale Operating Mode                 : Custom
    |--- Edit Custom (O)peration Mode Settings
  ( 4) : Configure this Router as Exit Node           : No
  ( 5) : Advertise Routes on this router              : Yes (192.168.9.0/24)
  ( 6) : Enable Site-to-Site functionality on router  : No

 ---------------------------------------------------------------------------------------

  ( 7) : Custom configuration options for TAILMON
  ( 8) : Force reinstall Entware dependencies
  ( 9) : Check for latest updates
  (10) : Uninstall TAILMON
    |
  ( L) : Launch TAILMON in Monitoring Mode (sh /jffs/scripts/tailmon.sh)
  ( M) : Launch TAILMON in Monitoring Mode using SCREEN (sh /jf..ts/tailmon.sh -screen)
    |
  ( e) : Exit

 ---------------------------------------------------------------------------------------

Please select? (1-10, R/S/T/U/D/P/B/F/I/O/L/M, e=Exit): m
Messages:

Executing: tailscale update --track unstable

This will update Tailscale from 1.88.3 to 1.89.207. Continue? [y/n] y
Downloading "https://pkgs.tailscale.com/unstable/tailscale_1.89.207_arm64.tgz"
Download size: 30688885
Downloaded 32768/30688885 (0.1%)
GET "https://pkgs.tailscale.com/unstable/tailscale_1.89.207_arm64.tgz": downloaded 30688878, want 30688885

Restart Tailscale?
[y/n]: y

Messages:

Executing: tailscale down

Messages:

 Checking tailscaled...              alive.
 Shutting down tailscaled...              done.

Messages:

 Starting tailscaled...              done.

Messages:

Executing: tailscale up --advertise-routes=192.168.9.0/24,192.168.53.15/32


[Tailscale Service/Connection Successfully Restarted]

Press any key to continue...

 

[Viktor Jaep]

Hi Viktor,

Odd thing happening here, I cannot seem to update to the Tailscale Beta (anymore I think, life's a blur atm).
IIRC I updated it yesterday to whatever the latest unstable is, then downgraded it back to 1.88.3 and now I cannot seem to go back up to unstable track again?
I tried starting from within amtm, from the CL (just tailmon), in Monitoring Mode with screen, and without, same result?
It does the whole download install thing but keeps saying 1.88.3 at the end of it, each trial the same.
" Tailscale version" at the CL says 1.88.3.
There is a small discrepancy here "downloaded 30688878, want 30688885" but I am not sure if that is the issue.
I am in CUSTOM Mode btw, if that has aby bearing on it.

How can I get you logs to see what is happening?

Press any key to continue...
  TAILMON Main Setup and Configuration Menu

  Please choose from the various options below, which allow you to perform high level
  actions in the management of the TAILMON script.
 ---------------------------------------------------------------------------------------

  ( 1) : Install Tailscale Entware Package(s)         : Installed
    |--- (R)e-(S)tart / S(T)op Tailscale Service      |--- Started
    |--- (U)p / (D)own Tailscale Connection           |--- Connected
    |--- U(P)date Tailscale Binary to latest version  |--- v1.88.3
    |--- Update Tailscale Binary to latest (B)ETA
    |--- (F)orce Downgrade to Older Tailscale version
    |--- (I)ssue Connection '--reset' Command
  ( 2) : Uninstall Tailscale Entware Package(s)
  ( 3) : Set Tailscale Operating Mode                 : Custom
    |--- Edit Custom (O)peration Mode Settings
  ( 4) : Configure this Router as Exit Node           : No
  ( 5) : Advertise Routes on this router              : Yes (192.168.9.0/24)
  ( 6) : Enable Site-to-Site functionality on router  : No

 ---------------------------------------------------------------------------------------

  ( 7) : Custom configuration options for TAILMON
  ( 8) : Force reinstall Entware dependencies
  ( 9) : Check for latest updates
  (10) : Uninstall TAILMON
    |
  ( L) : Launch TAILMON in Monitoring Mode (sh /jffs/scripts/tailmon.sh)
  ( M) : Launch TAILMON in Monitoring Mode using SCREEN (sh /jf..ts/tailmon.sh -screen)
    |
  ( e) : Exit

 ---------------------------------------------------------------------------------------

Please select? (1-10, R/S/T/U/D/P/B/F/I/O/L/M, e=Exit): m
Messages:

Executing: tailscale update --track unstable

This will update Tailscale from 1.88.3 to 1.89.207. Continue? [y/n] y
Downloading "https://pkgs.tailscale.com/unstable/tailscale_1.89.207_arm64.tgz"
Download size: 30688885
Downloaded 32768/30688885 (0.1%)
GET "https://pkgs.tailscale.com/unstable/tailscale_1.89.207_arm64.tgz": downloaded 30688878, want 30688885

Restart Tailscale?
[y/n]: y

Messages:

Executing: tailscale down

Messages:

 Checking tailscaled...              alive.
 Shutting down tailscaled...              done.

Messages:

 Starting tailscaled...              done.

Messages:

Executing: tailscale up --advertise-routes=192.168.9.0/24,192.168.53.15/32


[Tailscale Service/Connection Successfully Restarted]

Press any key to continue...

The download functionality is purely Tailscale's. If it's not downloading correctly, they must have an issue with that package. I'd wait a day and try again, and hopefully they will have resolved it?

You can run that command by itself and see if you get the same result?

tailscale update --track unstable

 

[jksmurf]

tailscale update --track unstable

XX@RT-AX86U_Pro:/tmp/home/root#
XX@RT-AX86U_Pro:/tmp/home/root# tailscale update --track unstable
This will update Tailscale from 1.88.3 to 1.89.207. Continue? [y/n] y
Downloading "https://pkgs.tailscale.com/unstable/tailscale_1.89.207_arm64.tgz"
Download size: 30688885
Downloaded 512/30688885 (0.0%)
GET "https://pkgs.tailscale.com/unstable/tailscale_1.89.207_arm64.tgz": downloaded 30688878, want 30688885
XX@RT-AX86U_Pro:/tmp/home/root#

It only downloads it, no install ("downloaded" vs "want" shows the same numerical disrepancy though).
So just like yours → TS problem.

 

[Viktor Jaep]

XX@RT-AX86U_Pro:/tmp/home/root#
XX@RT-AX86U_Pro:/tmp/home/root# tailscale update --track unstable
This will update Tailscale from 1.88.3 to 1.89.207. Continue? [y/n] y
Downloading "https://pkgs.tailscale.com/unstable/tailscale_1.89.207_arm64.tgz"
Download size: 30688885
Downloaded 512/30688885 (0.0%)
GET "https://pkgs.tailscale.com/unstable/tailscale_1.89.207_arm64.tgz": downloaded 30688878, want 30688885
XX@RT-AX86U_Pro:/tmp/home/root#

It only downloads it, no install ("downloaded" vs "want" shows the same numerical disrepancy though).
So just like yours → TS problem.

Not sure where this file ends up, but maybe it's clogging itself up in your /tmp folder? If you see it in there, maybe delete it and try that command again?

 

[jksmurf]

Not sure where this file ends up, but maybe it's clogging itself up in your /tmp folder? If you see it in there, maybe delete it and try that command again?

Well there was a file in there (good call) but...deleting it didn't help...it just got stuck back in there again.
I will see if they have a better file next update... .

Was just testing the beta due to the various messages I am seeing (above posts).

 

[fisk]

Recently had an issue with Tailscale on Merlin, trying to connect my phone and mobile devices to Jellyfin and Audiobookshelf. It just doesn't work.

This was - in my case - due to the fact that IP Forwarding was not enabled. Unfortunately, the Tailscale documentation suggests that you modify /etc/sysctl.d - but there is no sysctl.d on Merlin. So, instead, you need to:

echo 1 > /proc/sys/net/ipv4/ip_forward
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding

Then, to make it permanent after reboot, modify /jffs/scripts/init-start, adding the following two lines:

#!/bin/sh
echo 1 > /proc/sys/net/ipv4/ip_forward
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding

I was surprised this wasn't an automated option in TAILMON, nor was it anywhere in the documentation (that I found - I've been digging around all over the place - I found this information here).

an aside - thanks for all the work. TAILMON is rad.

 

[Viktor Jaep]

Recently had an issue with Tailscale on Merlin, trying to connect my phone and mobile devices to Jellyfin and Audiobookshelf. It just doesn't work.

This was - in my case - due to the fact that IP Forwarding was not enabled. Unfortunately, the Tailscale documentation suggests that you modify /etc/sysctl.d - but there is no sysctl.d on Merlin. So, instead, you need to:

echo 1 > /proc/sys/net/ipv4/ip_forward
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding

Then, to make it permanent after reboot, modify /jffs/scripts/init-start, adding the following two lines:

#!/bin/sh
echo 1 > /proc/sys/net/ipv4/ip_forward
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding

I was surprised this wasn't an automated option in TAILMON, nor was it anywhere in the documentation (that I found - I've been digging around all over the place - I found this information here).

an aside - thanks for all the work. TAILMON is rad.

Thanks for sharing! This isn't something I've ever needed to do, nor have I heard anyone else running into this issue, and needing to use a fix like this. Unless it's already on by default on our routers? I'll need to check.

 

[fisk]

Thanks for sharing! This isn't something I've ever needed to do, nor have I heard anyone else running into this issue, and needing to use a fix like this. Unless it's already on by default on our routers? I'll need to check.

Unsure why my setup might be strange. I'll note that it caused really difficult to diagnose effects, namely everything looked right in Tailscale status, and everything could connect (directly), but the latency was huge. Both Symphonium (connecting to Jellyfin) and Audiobookshelf were effected. Couldn't listen to more than ~30s of audio without buffering.

I realized I forgot to add the direct link to the Tailscale documentation.

 

[Viktor Jaep]

Recently had an issue with Tailscale on Merlin, trying to connect my phone and mobile devices to Jellyfin and Audiobookshelf. It just doesn't work.

This was - in my case - due to the fact that IP Forwarding was not enabled. Unfortunately, the Tailscale documentation suggests that you modify /etc/sysctl.d - but there is no sysctl.d on Merlin. So, instead, you need to:

echo 1 > /proc/sys/net/ipv4/ip_forward
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding

Then, to make it permanent after reboot, modify /jffs/scripts/init-start, adding the following two lines:

#!/bin/sh
echo 1 > /proc/sys/net/ipv4/ip_forward
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding

I was surprised this wasn't an automated option in TAILMON, nor was it anywhere in the documentation (that I found - I've been digging around all over the place - I found this information here).

an aside - thanks for all the work. TAILMON is rad.

So weird thing, @fisk ...

I already had a /proc/sys/net/ipv4/ip_forward file that contains a "1". So that must be why it's working for me and others without issue. But I don't have an init-start file that actually rewrites this each time the router boots. So it must be there by default for some reason?

I don't use ipv6, so that file wasn't there. EDIT: I didn't go down my path completely... it was there after all (maybe from a time when I did have IPv6 running), but it was also set to "1".

Anyways... interesting. I'm sure someone knows the answer why this is the way it is... I'm sure.

 

[jksmurf]

I don't use ipv6, so that file wasn't there.

I use both ipv4 and ipv6. Mine have nothing in them at all.
No 1s or 0's. Maybe they are non-binary...

k.

 

[buis]

What is your advice for putting the code in SSH?

 

[jksmurf]

What is your advice for putting the code in SSH?

Which code are you referring to exactly please?

If it is a CMD argument in Tailscale (via Tailmon) you cab use Tailmon's Custom menu to revise this.

But again, I am just guessing what code you are referring to at this point, you're going to need to be much more precise as to what code you mean please, for what purpose. Thank you.

 

[Viktor Jaep]

I use both ipv4 and ipv6. Mine have nothing in them at all.
No 1s or 0's. Maybe they are non-binary...

I'm pretty sure if it's blank, then it's disabled. "1" = enabled. But things seem to be working fine for you... so this is a real headscratcher. I'm not sure how these were enabled on my system, and seeing that I don't need to use the "init-start" method to keep them permanently enabled, they must be enabled by default somehow?

 

[ColinTaylor]

I use both ipv4 and ipv6. Mine have nothing in them at all.
No 1s or 0's. Maybe they are non-binary...

"Files" in /proc are not regular files. They are virtual constructs used to read or write kernel values. Trying to open them in an editor will not work. You have to read or write to them using commands like cat and echo.

 

[Viktor Jaep]

"Files" in /proc are not regular files. They are virtual constructs used to read or write kernel values. Trying to open them in an editor will not work. You have to read or write to them using commands like cat and echo.

@ColinTaylor ... what is your opinion on this situation above? Why would these values be blank for @fisk, where he has to enable them each time in the init-start, yet for me, they seem to be on by default, no init-start needed?

 

[jksmurf]

they must be enabled by default somehow?

No idea sorry.

"Files" in /proc are not regular files. They are virtual constructs used to read or write kernel values. Trying to open them in an editor will not work. You have to read or write to them using commands like cat and echo.

So both 1 for me, using cat. Thanks to Colin.

ASUSWRT-Merlin RT-AX88U_PRO 3006.102.6_alpha1-gc3ecf6dda6 Thu Oct 16 22:03:44 UTC 2025
XXXXXXX@RT-AX88U-Pro:/tmp/home/root# cat /proc/sys/net/ipv4/ip_forward
1
XXXXXXX@RT-AX88U-Pro:/tmp/home/root# cat /proc/sys/net/ipv6/conf/all/forwarding
1
XXXXXXX@RT-AX88U-Pro:/tmp/home/root#

 

[ColinTaylor]

@ColinTaylor ... what is your opinion on this situation above? Why would these values be blank for @fisk, where he has to enable them each time in the init-start, yet for me, they seem to be on by default, no init-start needed?

As far as I know Merlin specifically sets the kernel values in the firewall code:

asuswrt-merlin.ng/release/src/router/rc/firewall.c at 9def7bc5f81986dfec82e56cd0f9665f130be88b · RMerl/asuswrt-merlin.ng

Third party firmware for Asus routers (newer codebase) - RMerl/asuswrt-merlin.ng

github.com

So unless he's not in "router mode" I can't think why it wouldn't be set.

 

[jksmurf]

As far as I know Merlin specifically sets the kernel values in the firewall code:

I continue to be floored by @ColinTaylor just coming up with this stuff 99 times out of a 100.
Must have the entire subdirectory structure memorised and the Merlin code on speed-dial...

 

[ColinTaylor]

I continue to be floored by @ColinTaylor just coming up with this stuff 99 times out of a 100.
Must have the entire subdirectory structure memorised and the Merlin code on speed-dial...

Ha! Not really. The kernel IP forwarding was something I was aware of when I wrote the wiki. I thought long and hard about whether to include mention of those but decided against it as I regarded as unnecessary and an edge case at best. The main purpose of the wiki was to keep it as simple as possible for 99% of users and point people to the official documentation for everything else.