TCP connection pauses for a long time then restarts - tcp

I have an ubuntu 18.04 vbox hosted on a windows PC and bridged to the gigabit wired connection.
From chrome running on the windows PC I invoke a graphql api on the Ubuntu VM. The graphql returns about 3MB of data and everything is working fine.
The windows PC is in a DMZ and I can invoke the graphql API from another PC in another place (remotely). Iperf3 tells me that I have about 10-15 Mbit/s bandwidth when connecting remotely.
Anyway, when I try to invoke the graphql API it happens that the TCP connection (on port 4000) after transferring about 700kB seems to pause for a long time (about 70-80 secs) and the it restarts. Sometimes all the transfer is performed but not all the times.
This is a capture that shows the "pause":
I played with the TCP window size (reducing it) to no avail.

I did several tests with different web servers, also with an Ubuntu VM using VMWARE and finally I got the problem. I had to remove "LiveQoS NDIS 6 Filter Driver" from the windows ethernet interface stack.
This "LiveQoS NDIS 6 Filter Driver" causes many problems when using virtual machines.
If you need other info I will be glad to help.

Related

How to ssh into a work laptop connected to a VPN

I haven't found a question fitting the exact parameters of my situation (please excuse me if I have missed it).
For the last year remote work has been nothing but a blessing, it's the perfect set-up for me and my productivity has skyrocketed. The one blemish I'm still facing is when it comes to accessing work apps and machines (via ssh) for which a connection to the work network is required.
For that I use my work laptop and assorted VPN connection (using F5 Big IP) while most of my dev work/meetings/emailing/etc takes place on my comfortable personal desktop. Working on the work laptop is a miserable affair, it has a tiny, low-res, TNT, 12" panel while my personal PC has two 27" displays.
I would very much like, on the personal PC, to be able to use a dedicated browser plugged into an ssh tunnel running on the laptop to access work-network only apps and to ssh into work machines.
Both machines are running Windows 10, which is fine for my personal PC as all my dev work takes place through WSL2/Docker but is really painful on the work laptop because it's a pre-WSL2 version.
Both PCs use my home wifi connection, through which the work laptop connects to the VPN.
I'm wondering how to go about achieving that ssh tunnel to the work laptop since, once connected to the work VPN, the laptop isn't visible anymore on the local network.
I've been thinking of trying to hook them up via ethernet and use that second connection as the support for the ssh access but I'm not sure that'd work or how to go about it.
Any help would be much appreciated, thank you for taking the time to read this.
Setup a Reverse SSH Tunnel
In short you connect from your laptop to your Windows10 Box using ssh.. (You will need to run sshd on Windows 10) either via Windows or via cygwin or a virtual machine. Once you have that working you can use the OpenSSH "Reverse tunnel" feature which binds a port on your Windows Box and when your connect to it that opens a connection to your Laptop.
This example uses port 22 but you could use any TCP based port. (e.g. 3389 is RDP)
Let's assume that Destination's IP is 192.168.20.55 Laptop that you want to access).
You want to access from Windows10 desktop with IP 138.47.99.99.
Destination (192.168.20.55) <- |NAT| <- Source (138.47.99.99)
SSH from the destination to the source (with public IP) using the command below:
ssh -R 19999:localhost:22 sourceuser#138.47.99.99
port 19999 can be any unused port.
Now you can SSH from source to destination through SSH tunneling:
ssh localhost -p 19999
3rd party servers can also access 192.168.20.55 through Destination (138.47.99.99).
Destination (192.168.20.55) <- |NAT| <- Source (138.47.99.99) <- Bob's server

Unable to connect two telscale ss7 instances initiated on two different centos machines

I am trying two connect two machines using ss7 protocol. I am very much new in the field and has almost very little knowledge.
I have restComm-jss7-7.1.1.1385 telscale simulator.
I want to initiate testerHost on one machine and access it from a different machine on same LAN. What I'm trying to do is that I'm trying to run ATI client on one machine and ATI Server on the other how can I do so. Would be thankful for any help. I'm using CentOS 7 on both PCs.
The problem I was facing was actually the firewalld of CentOS 7 and SELinux as well were creating issues. I disabled them because they were blocking the ports and as soon as I disabled firewalld and SELinux, the M3UA layer got connected and thus both the instances were working fine.

WSO2 Identity Server hangs after "Using java memory" line

I had installed WSO2 Identity Server V5.2 on a VirtualBox machine, and it was working fine.
Then, I was doing some network testing/reconfiguration on my home network, where I was trying to separate my development (virtual) machines from my main in-home LAN by having the machine that was hosting VirtualBox connect wirelessly to a small router (a TPLink TL-WR702N) in a Bridge configuration, where the TPLink is connecting to my main WIFI network and then also exposing itself as a different WIFI network).
I was doing this testing because I am going to be working from a different location for awhile, and I wanted to isolate my dev machines while I was there and I only will have WIFI, and no hardwired connection, so I wanted to see if I could bridge wirelessly.
That machine hosting VBox started up ok and actually, the WSO2 machine also came up ok, but then when I tried to start the WSO2 IS (./wso2server.sh), it would output the 1st 3 lines and then hang on the 3rd line which was "User Java memory...".
If I move the hosting machine back to my normal LAN (i.e., not on the "bridged" network), everything works fine.
I noticed that when the hosting machine was on the bridged network, I couldn't ping the network gateway (192.168.0.1) from the VBox guest machines.
Would that cause the WSO2 to hang during startup? What else might be causing this problem?
Thanks,
Jim
I think that the problem was that WSO2 IS seems to need to be able to resolve the hostname during startup, and that was combined with needing to (apparently) bounce the machine to get the networking working. After the bounce, the networking seemed to get straightened out and then the WSO2 IS was able start ok.

Network adapter not working after a couple of minutes Windows Server 2012

we have been trying to solve a strange problem for the last 2 days but after a lot of searching we are stuck at the same point. We previously had Windows Server 2012 and it was working great, no problems, but decided to upgrade to R2 and that's where all our problems started.
Server:
HP PorLiant ML310e Gen8
2 Network cards ( Broadcom NetExtreme Gigabit Ethernet )
Windows Server 2012 R2
Clients:
Windows 8.1 Pro
We use one of the network cards for the server and the other for a virtual machine in Hyper-V. When the server was updated, all users, groups and permissions where created and assigned, so every member of the network could join their computers with their new users and passwords (no problem here), but when clients try to access the shared folders of the network they are unable to do so. And they can't ping the server.
So, the deal is that when the server is just started (or restarted) every client can see the network directories, can ping the server, everything works just fine for 2 or 3 minutes, then the network falls apart and there is no way for us to bring it back up other than restarting the server, but again it only works for like 3 minutes.
If we try to ping the server's IP address we get the 'General Failure' Message.
We have tried:
Enabling and disabling network adapters
Changing the order of the network adapters
Hyper-V is not being started
Disabling Network Load Balancing (NLB)
Disabling Large Send Offload (LSO) both with netsh and in the card's properties
Change the network adapter static IP
Disabling IPv6
Disabling the 'Allow the computer to turn off this device to save power'
Also noted that the server is getting several IP addresses from the DHCP. We have Microsoft Dynamics CRM 2013, and SQL Server 2012 installed.
Can any of you guys please help us with this situation? we'll be very grateful :)
Thanks in advance!
Greetings!
Ok,so this was an ol' windows trick... no matter what configuration we tried, windows server kept taking down the network minutes after it was started, so we:
Completely uninstall both network adapters
Restarted the server
Did the standar network adapter configuration (static IP addres, network, gateway, set the virtual switching for Hyper-V)
And everything started working again. So we kept the same configuration as before; Windows just needed to install the network adapters again.
Greetings!

VMWare Fusion 6.0.2 Network Bridging is allowing only certain specific traffic

I am using OSX Mavericks and VMWare Fusion v6.0.2.
I am running two Virtual machines, one Windows 7 Pro, and the other Debian Sid.
I do not wish to use NAT networking through the Host, I prefer to have the VMs sitting directly on the network, but I am having a problem getting the bridged networking functionality of VMWare Fusion working correctly. I have set the VMWare Network preferences page to Bridge the VMs to the Mac internal WiFi adapter.
Both VMs can ping the router, and they both get valid DHCP assigned IP addresses for the LAN. They can both connect to the Internet over the network bridge and browse and download files.
My problem is when I wish to communicate between the VM->Host, Host->VM, or VM->VM over other ports. For example if I try to SSH from OSX Host to the Debian VM, the request times out. The Windows 7 VM has a SQL Server running on it, but I cannot connect to it from the OSX host, or from the Debian VM. The Debian VM has a xsp4 web-server running on port 8080, but neither the OSX host nor the Debian VM can access it.
I can ping from Host->VM, VM->Host, and VM->VM with no issue, they can all see each other on the network, and the OSX host is sharing network folders to the Windows 7 VM without a hitch. It seems like it is allowing some communication, such as DHCP requests, Ping requests, Windows Network Shares, and Web Browsing, but is not allowing anything else.
I have turned off the Windows Firewall, OSX Mavericks firewall is turned off, and the Debian VM doesn't have selinux or iptables firewalls installed.
I have found several similar question threads while researching this problem, but a lot of them are for much older versions of VMWare Fusion, or are for VMWare Workstation which has different network preferences.
I can get these scenarios working to a degree if I switch VMWare's network settings to use NAT instead of bridging, but that messes up the IP addresses of the VMs, I want to keep them on the same network.
For what its worth, I did eventually come up with an answer for this.
There are two different versions of VMWare Fusion 6.x, Standard and Professional.
I was using the Standard version.
I changed the licence for a Professional licence, which allows you to add new network configurations in VMWare Preferences (and other cool things like that).
I added a new network with the default options, then assigned all of my VMs to that new network interface. I also turned on Promiscious mode in settings, but that might not have changed anything.
I then rebooted the VMs, set them up correctly to work on their new IP addresses, and Lo and Behold, I was able to establish connections between VM->Host and VM->VM. Exactly what I wanted.
I realize that this post is several years old, but since I had such a hard time with an issue similar to this, I wanted to post my answer as well, though I am not positive it really solved my issue. No problems still.
My setup:
MacBook Pro (Retina, 15-inch, Mid 2015)
OS X El Capitan
My problem:
In order to allow me to clone my private school git repository using ssh keys, I have to run a bridged network connection for my Windows 10 Eduction VM using VMWare Fusion.
What I've Tried:
http://www.kapilarya.com/windows-sockets-registry-entries-required-for-network-connectivity-is-missing
https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1016466
And several other blog posts and forum replies, all attempting to do somewhat the same thing.
Answer:
After numerous attempts to reset just about everything you could, I took a step back and brainstormed. Then I thought, if my host machine (Macbook Pro) could connect wirelessly to the internet, this bridged connection should still work. I checked the Network Adapter's MAC Assigned to the VM's Network Adaptor and it was different from my host computer's wifi address (MAC Address). I then entered my host machine's wifi network address (MAC Address) in as the effective MAC Address for the Windows VM Network Adaptor and..voila, internet.

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