Calibre-Server and Port Forwarding Issues

[MontyJ]

Hopefully this is the right subsection for this topic? I realize this is not a 'router' oriented site, but perhaps some of you have gone through similar issues getting the Calibre-Server to work and have some tips!

Ok, have the latest manual bin install of Calibre on Mint Linux. Trying to setup port forwarding so I can share the my library. The Calibre-Server appears to work great, and I can test it using Port 8181. I can also log in using another PC on the local network, so that part appears ok.

And, using netstat, I can see that port 8181 is "Listening"

The problem does appear to be how to set up port forwarding so the server can be seen from the Internet.

I have setup port forwarding in the router to forward to 192.168.5.xxx:8181, which is the static IP address of the Linux PC.

Then using a web based testing site, I tested my external IP address and port 8181, but it says it is closed.

I then just just turned on full DMZ in the router for the Linux PC IP address. Still nothing using the web test site.

My setup is through a Megacable ISP modem > Asus RT-N16 Tomato 1.28 based router.

Any thoughts on where the problem could be?

My router WAN section shows:

Connection Type DHCP
IP Address 192.168.0.xx
Subnet Mask 255.255.255.0
Gateway 192.168.0.x
DNS 8.8.8.8:53, 8.8.4.4:53
MTU 1500

But those setting are different than my LAN settings which are:

Router IP 192.168.5.xxx
Gateway 192.168.5.xxx (points to router)

Is it possible the ISP modem is somehow blocking things because it is using a different IP for the router? I have so far discounted that because this setup, w/o port forwarding, has been going fine for years, although the Linux install is fairly new.

It must be something simple I am missing, LoL.

Thanks for any ideas I can try!

[theducks]

the 3rd octet does not match (5 vs 0)

Port forwarding works most reliably with either a reserved or static IP assigned to your server.

Ip you 'server' is a portable, you really want to have the router reserve the IP
How this is set varies by router brand, but usually needs the MAC address of the server

[PeterT]

I'm somewhat suprised that Tomato says your WAN settings are 192.168.5.xxx; 192.168.x.x addresses are "non routable" on the internet. (See https://en.wikipedia.org/wiki/Privat...address_spaces ).

If you visit https://www.whatismyip.com/ what IP address is shown?

[MontyJ]

Thanks guys!

Yes, the IP for the PC the Calibre Server is running on is set STATIC.

The octet difference is why I asked the question about the ISP modem somehow not letting the requests through because they think it is a .0.xx but on my LAN it is a .5.xx.

My external IP at any IP check site is my normal one assigned by Megacable: 200.66.xxx.xxx. This has not varied in 6 months, so it is almost as good as a static assignment. But it is consistent which is what I am looking for.

As I understand port forwarding, from the internet, someone should be able to simply type in the 200.66.xxx.xxx:8181 and if my port forwarding is setup/working correctly, they should see the Calibre Server login screen. But that is not happening.

Unless someone can see something else, I am left with resetting my local LAN to match what the dang Megacable modem is trying to force my router to, ie set my router address to the 192.168.0.xx address.

That is a pain as I have 30 or so devices on the networkI have to change the IP's on and reset all the static assignments for as well. But then at least the router's address will agree with what the modem is trying to set.

Again, that difference has never been a problem in the past for any network or Internet activities, using P2P stuff like Teamviewer, etc. Just it seems the only thing left for me to try for this Port Forwarding thing.

Other ideas?

Thanks!

[davidfor]

If the port forwarding on the router is configured correctly, it is probably your ISP. Some will block external access to most ports. Some will only block 25, others "known ports", some others everything except those "known ports" and then others just about everything. Things like Teamviewer will run because the connection is started from inside the network over ports 80 and 443. With this, you are actually communicating via the Teamviewer server.

Looking at the WAN settings, that suggests the ISP isn't allocating you an public IP address. That looks like they are using private IPs and then NATing them in their network. Or do you have another router or modem between this one and the ISP?

You might get some information by doing a traceroute from your PC to some external IP. How useful it will be depends on the devices along the way being configured to respond properly.

[PeterT]

I bet what you need is to set your ISP supplied modem to Bridged mode as opposed to its default of Routed mode.

[MontyJ]

Originally Posted by davidfor

If the port forwarding on the router is configured correctly, it is probably your ISP. Some will block external access to most ports. Some will only block 25, others "known ports", some others everything except those "known ports" and then others just about everything. Things like Teamviewer will run because the connection is started from inside the network over ports 80 and 443. With this, you are actually communicating via the Teamviewer server.

Looking at the WAN settings, that suggests the ISP isn't allocating you an public IP address. That looks like they are using private IPs and then NATing them in their network. Or do you have another router or modem between this one and the ISP?

You might get some information by doing a traceroute from your PC to some external IP. How useful it will be depends on the devices along the way being configured to respond properly.

There is only the ISP modem connected to my router. After that is the cable out to their local switch location.

Maybe a call to tech support at Megacable would find that out for sure and get any port blocking unblocked. Here is a traceroute in Linux to Megacable.com.mx, 200.52.196.125:

traceroute to 200.52.196.125 (200.52.196.125), 30 hops max, 60 byte packets
1 unknown (192.168.5.xx) 0.268 ms 0.375 ms 0.350 ms (my router's LAN IP)
2 192.168.0.1 (192.168.0.1) 0.793 ms 0.807 ms 0.783 ms (my router's WAN IP?)
3 10.46.0.1 (10.46.0.1) 8.292 ms 8.288 ms 8.263 ms (Modem IP Address?)
4 10.0.44.62 (10.0.44.62) 9.178 ms 9.215 ms 9.191 ms
5 customer-GYS-static-161-9.megared.net.mx (200.52.161.9) 10.720 ms 11.174 ms 10.744 ms
6 pe-gys.megared.net.mx (189.199.117.133) 10.702 ms 10.540 ms 10.542 ms
7 10.3.0.25 (10.3.0.25) 47.652 ms 45.382 ms 45.351 ms
8 10.3.0.13 (10.3.0.13) 45.814 ms 47.297 ms 47.664 ms
9 10.3.1.17 (10.3.1.17) 49.101 ms 49.413 ms 49.970 ms
10 10.3.0.97 (10.3.0.97) 49.133 ms 49.109 ms 49.888 ms
11 10.3.1.186 (10.3.1.186) 46.977 ms 46.955 ms 46.854 ms
12 10.3.1.42 (10.3.1.42) 50.515 ms 50.452 ms 45.425 ms
13 10.2.57.5 (10.2.57.5) 44.392 ms 10.2.57.1 (10.2.57.1) 45.081 ms 10.2.57.5 (10.2.57.5) 45.811 ms
14 * * *
15 portalweb.megacable.com.mx (200.52.196.125) 71.109 ms 68.393 ms 68.418 ms

Sure awfully busy there for the same domain traceroute to my ISP!

[davidfor]

Originally Posted by PeterT

I bet what you need is to set your ISP supplied modem to Bridged mode as opposed to its default of Routed mode.

Of course. I missed this completely in the first post:

Originally Posted by MontyJ

My setup is through a Megacable ISP modem > Asus RT-N16 Tomato 1.28 based router.

The external address is on the modem. The port routing has to be done on it. But, it will need to be routed to the ASUS routers address and that needs to forward it to the PC.

Or, as PeterT said, put the modem into bridged mode and let the ASUS router control the connection.

[MontyJ]

Originally Posted by davidfor

Of course. I missed this completely in the first post:



The external address is on the modem. The port routing has to be done on it. But, it will need to be routed to the ASUS routers address and that needs to forward it to the PC.

Or, as PeterT said, put the modem into bridged mode and let the ASUS router control the connection.

Hmmm, I have a setting in Tomato firmware for:

TomatoVPN (No VPN currently being used! Didn't want to complicate things at this point!)
WAN / Internet
Type: DHCP (a STATIC setting is available?)
MTU : 1500
Route Modem IP: 0.0.0.0 (must be in different subnet to router, 0.0.0.0 to disable)

Could that "Route Modem IP" setting possibly help? I am not sure what it is for...

[PeterT]

You have to reconfigure the modem / router supplied by Megacable.

Search for "megacable modo bridge" and the brand of your modem / router.

[PeterT]

That setting you have listed is just there to ensure that you can access the setup screen(s) on your modem itself.

For instance, I also have an RT N16 and Tomato. My cable modem is in bridged mode. |I has an internal IP address of 192.168.100.1; my rotuer is 192.168.2.1 and all devices onmy LAN are 192.168.2.2 - 192.168.2.254.

That checkbox just ensures that from my devices on the LAN I can access the modem config on 192.168.100.1

[MontyJ]

Well, I am able to log into the ISP Router...NOT modem! My bad!! I had it replaced a few months back and had forgotten he had given me a 4 port wireless Cisco router rather than the single port modem I had then.

Anyway, I can login and it looks like I can change some things, but not all. I tried a password change and it would not take, LoL.

I don't see any setting for "Bridged Mode". I have read the only way to do this is via telnet, which I may try if nothing else works. But I cannot give up my Tomato based router because it has OpenVPN in it and I need the VPN function that is router based.

Thanks for the awesome help!

Monty

[PeterT]

What is the brand / model of the ISP router? I'll look for a manual for it....

[MontyJ]

Originally Posted by PeterT

What is the brand / model of the ISP router? I'll look for a manual for it....

The router is a Cisco DPC3928S.

I tried to use telnet to get in, but the login was not the same as the router login. After 3 tries I got the msg that "telnet has been locked", LoL. Good o'le Megacable. I cannot change the router login, nor can I change the Static DNS settings. When I try to "Save" any of those, the router reboots and comes back up with their defaults back in. I am surprised I was able to change the wireless password in it. So, no bridged mode that I can see.

It appears to let me change the port forwarding, so here is what I tried, based on this guide: portforward.com/help/doublerouterportforwarding.htm

----------------------------------------------------
Cisco Modem/Router-

Local IP = 192.168.0.1 (default)
DHCP On, Range 192.168.0.10 (default)
Max Range DHCP Users = 119 (default)
Connected Devices = 192.168.0.11 (My Asus Router's 'external IP address')

Port Range Forwarding = 8181, 8282, 8383 to IP 192.168.0.11 (my router)
Note: 8181 is the only one I have in use by Calibre at this point. But when/if I can get this working, I will use the terminal mode to launch 3 Calibre-Server sessions for the 3 separate libraries I want to share

Asus RT-N16-

External IP = 192.168.0.11
Local IP = 192.168.5.15
Port Forward = 8181, 8282, 8383, to IP 192.168.5.168 (My Linux PC with Calibre)
-----------------------------------------------------

I have attached screenshots of the Port forward settings in the Cisco and Asus routers.

But, this setup does not appear to work. Checked it with grc.com and it says the ports are "stealthed", which means they are not showing as open.

And I checked it with yougetsignal.com and they are not showing open their either.

I did remove the default Mint Linux firewall and installed the firewall-applet from Red Had, and added the 8181 port only for now for testing.

That didn't help, so I saved the firewall settings and stopped it totally. Still no cigar...

So, still stuck...

[davidfor]

The screen shots look good. Or at least, they look like what I would do. But, as it isn't working, something is wrong.

The first thing I would do is connect the PC directly to the Cisco modem and set the rules to point to it. That will eliminate the ASUS router as the problem. If you still can't see anything, then it probably means the ISP is blocking the ports. Or there is a firewall on the modem blocking access.