The Wiert Corner – irregular stream of stuff

Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

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Archive for the ‘Internet protocol suite’ Category

How to copy files from one machine to another using ssh – Unix & Linux Stack Exchange

Posted by jpluimers on 2016/10/25

I’m using Linux (centos) machine, I already connected to the other system using ssh. Now my question is how can I copy files from one system to another system?

Source: How to copy files from one machine to another using ssh – Unix & Linux Stack Exchange

Nice question, uh? In my opinion the best answer is “Use scp to avoid going through hoops with complex configurations to re-use your existing ssh connection” like this:

To copy a file from B to A while logged into B:

    scp /path/to/file username@A:/path/to/destination

To copy a file from B to A while logged into A:

    scp username@B:/path/to/file /path/to/destination

Source: DopeGhoti answering How to copy files from one machine to another using ssh – Unix & Linux Stack Exchange

Instead the question is marked duplicate of SSH easily copy file to local system – Unix & Linux Stack Exchange where (contrary to the ‘easily’ part of the question) go through hoops and loops with all kinds of fancy ssh settings and port forwards.

Recursive

For recursive, use the -r option, as per [WayBack] shell – How to copy a folder from remote to local using scp? – Stack Overflow:

scp -r user@your.server.example.com:/path/to/foo /home/user/Desktop/

From man scp (See online manual)

-r Recursively copy entire directories

Related:

Read the rest of this entry »

Posted in *nix, *nix-tools, bash, Communications Development, Development, Internet protocol suite, Power User, Scripting, Software Development, SSH, TCP | Leave a Comment »

FileZilla on Windows is waaaay faster than WinSCP

Posted by jpluimers on 2016/10/21

Not sure why yet, but on a gigabit network between a Windows 2008 R2 Server and a Proxmox KVM machine, WinSCP gets around 10 megabit/second and FileZilla > 30 megabit/second.

Others seem to agree that filezilla faster than winscp.

–jeroen

Posted in Communications Development, Development, Internet protocol suite, Power User, Proxmox, SSH, TCP, Virtualization, VMware, Windows, Windows Server 2008, Windows Server 2008 R2 | 1 Comment »

Differences between SFTP and “FTP over SSH” – Stack Overflow

Posted by jpluimers on 2016/10/13

As I will likely have to secure some external FTP sessions soon and the endpoints the current FTP connects to are vague in what they support:

Here is the difference:

  • SFTP (SSH file transfer protocol) is a protocol that provides file transfer and manipulation capabilities. It can work over any reliable data stream, but is typically used with SSH
  • “FTP over SSH” uses the regular old FTP protocol, but an SSH tunnel is placed between client and server.

Source: Kristopher Johnson answering in c# – Differences between SFTP and “FTP over SSH” – Stack Overflow

–jeroen

Posted in Communications Development, Development, Internet protocol suite, Software Development, SSH, TCP, TLS | Leave a Comment »

TCP and the lower bound of web performance… is a must watch talk on plumbing,…

Posted by jpluimers on 2016/10/13

Thanks Ilya Grigorik for sharing this a long while ago:

TCP and the lower bound of web performance… is a must watch talk on plumbing, history, and people behind TCP. Awesome.

–jeroen

via: TCP and the lower bound of web performance… is a must watch talk on plumbing,….

Posted in Communications Development, Development, Internet protocol suite, Power User, TCP | Leave a Comment »

OpenSSH/Logging and Troubleshooting – 

Posted by jpluimers on 2016/09/19

For my own link history: Debugging a server configuration

Source: OpenSSH/Logging and Troubleshooting – Wikibooks, open books for an open world

Posted in Communications Development, Development, Internet protocol suite, SSH, TCP | Leave a Comment »

tombh/texttop: A fully interactive X Linux desktop rendered in TTY and streamable over SSH

Posted by jpluimers on 2016/08/09

Wonder if I can get this to work from macOS / OS X as a client:

texttop – A fully interactive X Linux desktop rendered in TTY and streamable over SSH

Source: tombh/texttop: A fully interactive X Linux desktop rendered in TTY and streamable over SSH

via: Kristian Köhntopp – Google+

Read the rest of this entry »

Posted in *nix, *nix-tools, Communications Development, Development, Internet protocol suite, Linux, Power User, Software Development, SSH, TCP | Leave a Comment »

Windows Flaw Reveals Microsoft Account Passwords, VPN Credentials

Posted by jpluimers on 2016/08/08

Attack from the ’90s resurfaces more deadly than before

Source: Windows Flaw Reveals Microsoft Account Passwords, VPN Credentials

TL;DR: block LAN->WAN port 445

Note this won’t affect web-dav shares like \live.sysinternals.com\DavWWWRoot as that uses ports 443 and 80.

–jeroen

via:

Posted in Communications Development, Development, https, Internet protocol suite, Microsoft Surface on Windows 7, NTLM, Power User, Security, SMB, TCP, WebDAV, Windows, Windows 10, Windows 7, Windows 8, Windows 8.1, Windows 9, Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, Windows Vista, Windows XP | Leave a Comment »

Writing tests for http / https request: Postman, SoapUI, Advanced REST client.

Posted by jpluimers on 2016/06/21

I’m using these Chrome Extensions for most of the http / https call mockups, and after that put them in SoapUI (which despite the name also does REST and has come a long way sinceSource: SoupUI – as sometimes that is the only thing that works):

You can get both Postman versions through GetPostman.com as well.

–jeroen

Posted in .NET, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, ASP.NET, C#, C# 3.0, C# 4.0, C# 5.0, Chrome, Communications Development, Development, Google, HTTP, Internet protocol suite, Power User, REST, Software Development, TCP | 1 Comment »

Latest Tumbleweed distribution update likely kills sshd

Posted by jpluimers on 2016/05/03

After a recent big update to OpenSuSE Tumbleweed, I could not ssh into my system any more.

Symptoms

The ssh client side would report a Read from socket failed: Connection reset by peer which I misinterpreted as the sshd not running at all.

Luckily the server is a VM, so I could reach the console. There I saw this:

sshd trying to load files it shouldn't

sshd trying to load files it shouldn’t

The files should not be loaded as they are not specified in the sshd_config file:

dsa and ecdsa not specified in the config file

dsa and ecdsa not specified in the config file

So I knew something was broken. After reading some messages in the forums.opensuse.org I got at Bug 977812 – sshd killed by SIGSYS on client connection

The cause

As usual with such issues the cause seems a combination of factors:

And we have the culprit, I believe: together with the glibc upgrade, openssl
was updated from 1.0.2g-1.1 to 1.0.2-2.12 which brought, among others, patch
openssl-urandom-reseeding.patch.

Temporary fix

A temporary fix is to comment out a line in /etc/sshd_config so you get this diff:

-UsePrivilegeSeparation sandbox # Default for new installations.
+# UsePrivilegeSeparation sandbox # Default for new installations.

Be sure to undo this as soon as you’ve received a final fix.

Final fix

A final fix is being fast-tracked so it appears in Tumbleweed soon.

I will report after deployment of [opensuse-factory] New Tumbleweed snapshot 20160502 released! as I think it contains the fix.

Aftermath

I already knew about openQA: Test summary which lists the builds, but not the changes in the builds.

Reading through Information Board or the like for Tumbleweed I found the openSUSE Mailinglist Archive: opensuse-factory which does the announcements and release notes for Tumbleweed.

It had both the announcement of the “big patch”, ssh bug report and temporary fix:

–jeroen

 

 

Posted in *nix, Communications Development, Development, Internet protocol suite, Linux, openSuSE, Power User, SSH, SuSE Linux, TCP, Tumbleweed | 2 Comments »

some more lsof, netstat and rpcinfo examples

Posted by jpluimers on 2016/03/07

Last friday I updated the examples at *nix networking – lsof: How to tell what process has a specific port open on Linux (via: Server Fault) as I needed to document some of the machines around here (so it becomes easier replacing them).

I also added some links to background information and (when I get to using it: OS X still goes without) a good iproute2 starter page.

–jeroen

Posted in *nix, *nix-tools, Apple, Communications Development, Cygwin, Development, Internet protocol suite, Linux, Mac, Mac OS X / OS X / MacOS, Mac OS X 10.6 Snow Leopard, MacBook, MacBook Retina, MacBook-Air, MacBook-Pro, MacMini, OS X 10.10 Yosemite, OS X 10.8 Mountain Lion, OS X 10.9 Mavericks, Power User, TCP | Leave a Comment »