Jason O's questions

I have a Windows program that connects to a COM port to send and receive data. The the other end is another program that is running on a remote Linux machine that also uses the COM port to communicate. I am trying to come up with the simplest way to bridge the connection between these two programs.

So far, I want to use the tty_bus utilities to create the COM port bridge over SSH. The problem I'm having is that I need to Windows side to have access to the bridged port. My thought was to create a virtual null-modem cable using com0com and then simply connect one end to my windows program and the other to the tty_bus utility on the Linux subsystem side. So, I tried creating a set of virtual COM ports using com0com and it "appears" that the COM port is not recognized by the Linux subsystem (or maybe I'm just doing something wrong). Is there a clean/better way to approach this?

I am using Radmin VPN to create a remote access VPN between my home and office computer. On the office computer, I created a network bridge (in windows) to bridge the VPN network connection with the LAN connection so that I can use remote desktop and SSH to access other computers on the office network from my home computer.

To do this, I first created the bridge by selecting the VPN connection, followed by the LAN connection and selecting "Bridge Connections". This created a network bridge which had an IP address on the same subnet as the other office computers. I then gave my home computer an additional IP address in the VPN connection that is on the same subnet as the office network computers. So far, I am able to ping the office computers and access Remote desktop and SSH from home. However, I am unable to directly ping or RDP into my office computer (the one hosting the VPN connection) when the bridge connection is enabled. When I try to ping it's LAN IP address, I get a "TTL expired in transit." error.

What does this mean and what can I do to fix it so I can also ping and RDP into my office computer? Everything else seems to work fine except for this.

I have an Ubuntu server running 18.04 LTS. Not long ago, I had to clone the drive of this server to another machine to make repairs, and now I need to reclone it back to the server again. This time, I used the GParted boot disk following these instructions here to copy the boot and EXT4 partitions from the second drive to the server.

After cloning the drive back. I tried to reboot the server but it just went into an infinite reboot loop after trying to start the drive. I'm assuming something got messed up with the grub configuration, so I next created a Boot-repair-Disk on a USB drive and followed these instructions here to try and repair Grub. Unfortunately, It failed, but I had it output the error report and posted it here:

http://paste.ubuntu.com/p/4gbg8F4xnH/

Onne user on the Ubuntu forum suggested that I clear the file system from the grub partition and try the Boot-Repair-Disk again. But I tried it and it still gave the same error: Here's an updated pastebin from the output:

http://paste.ubuntu.com/p/pGrtVWzWgm/

Here's what GParted shows for the curent partition setup:

I'm not sure what to try next. Any help appreciated.

I have an old Tripp-Lite UPS (SU2200RTXL2UA) which I need to communicate with via it's RS232 Port (this model doesn't have a USB port). I'm trying to figure out which Serial NUT driver would be most appropriate to receive communications from this UPS. The serial protocol is very simple, as explained by this excerpt from the user manual below:

Dry contact communications are simple, but some knowledge of electronics is necessary for configuration. The DB9 port's pin assignments are shown in the diagram. If the UPS battery is low, the UPS sends a signal by bridging pins 1 and 5. If utility power fails, the UPS sends a signal by bridging pins 8 and 5. To remotely shut down the UPS, short pin 3~pin 9 for at least 3.8 seconds.

When checking the list of available drivers for Tripp-Lite UPSs, I didn't see any Serial ones listed at all my model (or similar ones in the series). Are there any other generic serial UPS drivers that that would work for this scenario? I mainly just want to capture the signal from pins 8 and 5 being bridged so I can execute a script to shut down some servers which are attached.

NOTE: I'm using NUT with an Ubuntu 18.04 LTS server and a NAS running NAS4FREE (FreeBSD).

EDIT: After reviewing the NUT manual, it appears that the genericups driver with upstype=5 is the appropriate configuration that matches my UPS's RS232 pinout. Now, I just need to figure out how to set it up on my NAS through the GUI I'm using NAS4FREE.

My situation is almost identical to the one cited in this post:

How to change time source from "Local CMOS Clock" to "DC"

I have a domain-joined computer that is showing "Local CMOS Clock" as the source despite my attempts to change it. Here's what I've tried so far:

1. Ran the following terminal commands to confirm that the computer clock is off from the network server clock (by about two minutes): Net time /Domain:local.mydomain.com & Net time \\WORKSTATION-NAME

2. Ran the following command to confirm that the local machine set to "Local CMOS Clock": W32tm /query /source

3. However, running the following commands did not change the setting: w32tm /config /syncfromflags:domhier /update net stop w32time && net start w32time

4. Running W32tm /query /source still returns: “Local CMOS Clock”

What do I do now? I'm not sure how to force it to change.

I'm running into a weird problem while setting up a new SAMBA AD DC on my network. I've got the DC itself up and running and checked on the server that I am able to resolve the DNS name of the server, along with the Kerberos and ldap SRV records. I have its Internal DNS set to forward to my network's gateway, and all my client computers are configured to point their Primary DNS to the DC (I do not have any secondary DNS entries on the client computers).

The odd thing is, that from the clients, I can ping the DC from its IP address, NetBIOS name, or FQDN and all map to the correct IP address. But when I go to add the clients to the domain, I get an error complaining that the DC could not be contacted, with the following detail in the error box:

The following error occurred when DNS was queried for the service location (SRV) resource record used to locate an Active Directory Domain Controller (AD DC) for domain "local.foobar.com":

The error was: "DNS name does not exist." (error code 0x0000232B RCODE_NAME_ERROR)

The query was for the SRV record for _ldap._tcp.dc._msdcs.local.foobar.com

But if I SSH into the server and run:

$ host -t SRV _ldap._tcp.local.foobar.com
_ldap._tcp.local.foobar.com has SRV record 0 100 389 dc1.local.foobar.com.

I'm beginning to wonder if maybe I'm misunderstanding how the DNS Forwarder works. My understanding was that the clients (which are all pointing to the DC's DNS) would reference it first for DNS information, and then get forwarded along to the gateway's DNS if they don't find the entries they need. But it seems like they are not finding the existing SRV records In the DC's DNS (or they are just getting forwarded directly to the gateway, which I definitely did not add the entries too.... What do you think could be the problem here? Do I need to manually add the SRV records to the gateway or should the DC's internal DNS be responding to these requests?

P.S. As an aside, I did try entering the NetBIOS Domain name "LOCAL" and it seems to find the server and prompt me to enter the Administrator credentials and it lets me join the domain. I didn't go through with adding them this way though, as there is apparently a deeper issue here, but just wanted to mention this in case it could shine any light on the situation.