Xsmael's questions

I've set up PTR record on the DNS server of our organisation. Reverse lookup works on our network, but from a different network, it does not work.

It seems to me that something needs to be done on the regional Internet registry RIR's side.

I have no idea how to get in touch with them and then why would they do what I want?

Can I just configure PTR records and if I did it correctly it will just work?

Do I need the RIR to do something?

Is it how everyone is doing it?

PS: i'm comfortable with DNS but reverse DNS is kind of confusing to me for now (I'm new to it).

Say I have a domain name "my.domain.com" with an A Record that resolves to the public IPv4 address (say 160.200.200.21) of my server (running Ubuntu 20.04)

I've installed BigBlueButton on the server and almost everything is fine except that BigBlueButton needs to be able to reach itself from the domain name or public IP and there it fails and gives this error:

curl: (28) Failed to connect to  port 443: Connection timed out
# Error: Could not connect to the configured hostname/IP address

So i have done the following checks:

• Used netcat -l on port 80 and 443 with a remote server to make sure the ports are opened => SUCCESS

also the following commands i ran:

~# curl https://my.domain.com 
curl: (28) Failed to connect to my.domain.com port 443: Connection timed out

~# curl my.domain.com 
curl: (28) Failed to connect to my.domain.com port 80: Connection timed out

~# wget https://my.domain.com 
--2023-11-07 20:08:51--  https://my.domain.com/
Resolving my.domain.com (my.domain.com)... 160.200.200.21
Connecting to my.domain.com (my.domain.com)|160.200.200.21|:443... failed: Connection timed out.
Retrying.

But curl http://google.com responds!

Also note that the commands above work perfectly from another server or computer

~# netstat -anltp | grep :80
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      4082/nginx: master
tcp        0      0 127.0.0.1:52562         127.0.0.1:8021          ESTABLISHED 13903/node
tcp6       0      0 :::80                   :::*                    LISTEN      4082/nginx: master
tcp6       0      0 :::8021                 :::*                    LISTEN      13262/freeswitch
tcp6       0      0 127.0.0.1:8090          :::*                    LISTEN      13076/java
tcp6       0      0 127.0.0.1:32800         127.0.0.1:8021          ESTABLISHED 13745/java
tcp6       0      0 127.0.0.1:8021          127.0.0.1:32800         ESTABLISHED 13262/freeswitch
tcp6       0      0 127.0.0.1:8021          127.0.0.1:52562         ESTABLISHED 13262/freeswitch


~# netstat -anltp | grep :443
tcp        0      0 0.0.0.0:443             0.0.0.0:*               LISTEN      12628/haproxy
tcp6       0      0 :::443                  :::*                    LISTEN      12628/haproxy

At this point I don't know what to check again or where to look for the problem. This server is a virtual machine, provided by a provider so i only have ssh and root access provider said it was behind a firewall, but since the ports are clearly opened I don't know if they can be blamed.

So what is happening is my.domain.com is perfectly reachable outside the server(on browser or CLI) but not within the server even though the relevant ports are opened.

one thing I found weird, maybe the info will be useful: when I did netcat -l 80 on my server it worked even though Nginx was running on port 80. netcat -l 443 failed saying port is in use, i had to first shutdown the process using it before i could run the test.

I'm trying to enable IPv6 support on ubuntu 20.04 with no success

most resources i find online involve adding the following lines to /etc/sysctl.conf

net.ipv6.conf.all.disable_ipv6 = 0
net.ipv6.conf.default.disable_ipv6 = 0
net.ipv6.conf.lo.disable_ipv6 = 0

which i did, with no effect

or editting /etc/network/interfaces but this file does not exist on my system and i happen to have /etc/netplan/50-cloud-init.yaml i'm knew to netplan and cloud-init stuff. but when i opened the /etc/netplan/50-cloud-init.yaml it says the file is generated and any modification will be overwritten.

now how am I supposed to enable it IPv6 ? I don't need and IPv6 address, but i'm trying to install BigBlueButton 2.7 which is requiring IPv6 Support

I have some equipments in my LAN but the way things are working; I cannot set statics IPs for them, they really need to have DHCP enabled.

I am using Zabbix, and for host configuration, the Ip address is required; is there any way to go around this ?

I have pfsense and daloRadius(running freeRadius inside) up and running, I successfully configured radius parameters on pfSense and the NAS on daloRadius and they can talk to each other.

I am able to create users from daloRadius and authenticate them from pfSense. But when I add some attributes for bandwidth limitation or download quota limitation, authentication fails from pfSense.

Plus in spite of all the search i did, am' not able to understand clearly how radius attributes function: - Difference between check and reply and when to use either - also the operators being used.

Since i didn't understand clearly i tried all combinations that made sense to me but it never worked, I always get access-reject.

I added to daloRadius the pfSense radius attribute dictionary which i got from here:

VENDOR      pfSense             13644

BEGIN-VENDOR    pfSense

ATTRIBUTE   pfSense-Bandwidth-Max-Up        1   integer
ATTRIBUTE   pfSense-Bandwidth-Max-Down      2   integer
ATTRIBUTE   pfSense-Max-Total-Octets        3   integer

END-VENDOR pfSense

but whenever I create a user and try using one of these attributes in either reply or check attribute, the user is not authorised when logging in, just getting access-reject with no explanations.

What am I doing wrong ?

I've exported my VM from VMWare and tried importing it into XenServer (xcp-ng 7.6) XenConvert 2.1.1 but I always get this error:

Friday, May 24, 2019 11:15:04
XenConvert 2.1.1.2199 Copyright (c) 2001-2009 Citrix Systems, Inc.
Microsoft Windows 7 (Suite=0x00000100) SP 1
Processor Architecture: x64
Number of processors: 4
OVF to XenServer started at Friday, May 24, 2019 11:15:05
Validating OVF Package...
FWD: Warning:2019.5.24.11.15.5,181: Version not set, applying 1.0.0
FWD: Warning:2019.5.24.11.15.6,69: Validate VHS, Unknown hardware type: vmx-08 failing validation.
FWD: Error:2019.5.24.11.15.6,88: OVF Failed Validation, OVERRIDE return success
OVF Package is valid.
Source is C:\Users\RED\Documents\Virtual Machines\owncloudVMware-disk1.vmdk.
Destination is C:\Users\RED\Documents\Virtual Machines.
VMDK to VHD started at Friday, May 24, 2019 11:15:06
Converting VMDK to VHD...
Dismounting VHD...
Failed to find device for VHD with Id 6221 because of system error:  Element not found. (0x00000490)
Failed to get the system directory.
Windows directory is WINDOWS
Scanning for BOOT volume...
*** Warning! ***
Failed to find the Windows Boot Volume.
VHD C:\Users\RED\Documents\Virtual Machines\owncloudVMware-disk1.vhd was not configured for XenServer.
VM may not boot in XenServer.
Dismounting VHD...
VMDK to VHD stopped at Friday, May 24, 2019 11:34:45
Importing OVF Package...
FWD: Debug:2019.5.24.11.34.47,859: OVF.FindSystemIds completed, 1 found
FWD: Debug:2019.5.24.11.34.48,647: OVF.FindRasdByType completed, 1 found
FWD: Debug:2019.5.24.11.34.48,669: OVF.FindRasdByType completed, 1 found
FWD: Debug:2019.5.24.11.34.49,51: Import.Process: DefineSystem completed (bitnami-owncloud-10.1.1-2-r50-linux-debian-9-x86_64)
FWD: Debug:2019.5.24.11.34.49,376: Import.SetIfDeviceIsBootable: Using HostResource to find Disk
FWD: Warning:2019.5.24.11.34.49,388: Import.FindRasdleName: VHD file exists, replacing VMDK with VHD: owncloudVMware-disk1.vhd
FWD: Debug:2019.5.24.11.34.50,337: Found file owncloudVMware-disk1.vhd using VhdStream
FWD: Debug:2019.5.24.11.34.50,531: Import.UploadRawVDI Enter
FWD: Debug:2019.5.24.11.34.50,541: Import.UpdoadRadVDI SRUUID: 173cb437-4e01-4017-0ab4-4be4b9c8ecc2
FWD: Debug:2019.5.24.11.34.50,549: Import.UpdoadRadVDI Label: bitnami-owncloud-10.1.1-2-r50-linux-debian-9-x86_64
FWD: Debug:2019.5.24.11.34.50,560: Import.UpdoadRadVDI Capacity: 16000221184
FWD: Debug:2019.5.24.11.34.51,334: Import.UploadRawVDI::VDI Created
FWD: Debug:2019.5.24.11.34.51,430: Connect To: 160.226.184.91:80
FWD: Debug:2019.5.24.11.34.51,532: Request: PUT /import_raw_vdi?session_id=OpaqueRef:7227acf1-5a4f-48ef-9823-a3981632eec7&task_id=OpaqueRef:ef3459fe-551e-42c6-bed6-24470e11b6e0&vdi=OpaqueRef:f92c43f1-fa25-4b7b-9717-03f7a41f665a http:/1.0

FWD: Debug:2019.5.24.11.34.51,654: ERROR Returned: 400
FWD: Debug:2019.5.24.11.34.51,669: DoHTTP FAILED
FWD: Debug:2019.5.24.11.34.51,679: Import.UploadRawVDI::http.put complete
FWD: Debug:2019.5.24.11.34.56,687: Import.UploadRawVDI Leave
FWD: Debug:2019.5.24.11.34.56,706: OVF.Import.ImportFile leave
FWD: Debug:2019.5.24.11.34.56,717: Import.AddResourceSettingData, recevied autoevent, continuing
FWD: Debug:2019.5.24.11.34.56,717: Import.ImportFileProc (worker thread) completed
FWD: Debug:2019.5.24.11.34.56,725: Import.AddResourceSettingData VDI= OpaqueRef:f92c43f1-fa25-4b7b-9717-03f7a41f665a
FWD: Debug:2019.5.24.11.34.56,741: Import.VerifyUserDevice, checking device: 99
FWD: Debug:2019.5.24.11.34.56,843: Import.VerifyUserDevice, device: 99 will be used.
FWD: Debug:2019.5.24.11.34.56,848: Import.VerifyUserDevice, checking device: 99
FWD: Debug:2019.5.24.11.34.56,943: Import.VerifyUserDevice, device: 99 will be used.
FWD: Error:2019.5.24.11.34.57,39: VBD Create failed: VDI_READONLY
VDI_READONLY
Failed to import the OVF Package.
OVF to XenServer stopped at Friday, May 24, 2019 11:34:57

I followed this link: https://support.citrix.com/article/CTX116603

I've installed and configured pfsense 2.2.4

it works well and redirects unauthenticated users to the login page, as long as they use http; but when I type an https link the redirection doesnt work.

After lots of search I found that enabling https solves the issue but now i have an issue of certificates and users will always have that warning saying the web page is not secure. Which is unpleasant.

I found lately lets encrypt that gives free certificates. but This requires me to buy a domain name and for that i might need a public IP.( if i understand well)

All i need is that when a user is not authenticated, and type https://google.com it redirects it to the login page.

why i need this is because most modern browser will add https automatically without your permission.

I have a Linux machine with two network interfaces, and I'd like to get the IP address of the PPP interface w1g1 but it doesn't show up in ifconfig. There is a public IP on the PPP interface, but there is no internet connection, I'm trying to troubleshoot but I need to get the IP address of the interface and I can't.

ifconfig :

eth0      Link encap:Ethernet  HWaddr 00:30:48:8D:F0:2C
          inet addr:192.168.2.254  Bcast:192.168.2.255  Mask:255.255.255.0
          inet6 addr: fe80::230:48ff:fe8d:f02c/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:9970 errors:0 dropped:567 overruns:0 frame:0
          TX packets:4338 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          RX bytes:1441024 (1.3 MiB)  TX bytes:915814 (894.3 KiB)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:675 errors:0 dropped:0 overruns:0 frame:0
          TX packets:675 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:50659 (49.4 KiB)  TX bytes:50659 (49.4 KiB)

w1g1      Link encap:Point-to-Point Protocol
          UP POINTOPOINT RUNNING NOARP  MTU:240  Metric:1
          RX packets:748994 errors:0 dropped:0 overruns:0 frame:0
          TX packets:748992 errors:0 dropped:0 overruns:0 carrier:3
          collisions:0 txqueuelen:100
          RX bytes:179758560 (171.4 MiB)  TX bytes:179758080 (171.4 MiB)
          Interrupt:177 Memory:f881c400-f881e3ff

w1g1 is connected to a modem by an RJ45<->Serial cable and the modem is connected to the phone line. The modem is a NOKIA DNT2Mi you can see it here

Routing table :

192.168.2.0/24 dev eth0  proto kernel  scope link  src 192.168.2.254
169.254.0.0/16 dev eth0  scope link
default via 192.168.2.180 dev eth0

I'm experiencing a problem with my Cisco router 1900 Series, the router sometimes stop routing packets, and when i log into it and show the running-config i see no ip routing executing ip routing command does not solve the problem i have to reboot the router to make it work again. I thought this was an attack, but the problem persist even after changing all passwords and the time interval between each occurrence is very random! somtimes 15min somtimes couple hours or days.

I saw a discussion on cisco support forum which surprisingly started 6 days ago, (my problem is also recent, about 2 weeks)

Till now they didn't worked it out, I wanted to have your opinions and ideas, can a router in some circumstances or for some reasons disable his routing ? Have you ever experienced such a problem ? how did you solve it ?

Thanks!