Telnet alternative when you can't install telnet

I wanted to check the connectivity to an email service from a server that belongs to a client. I had restricted access to this server so I couldn't install new packages like Telnet.

If I had telnet it's much easier, but fortunately, the CURL package was already there. Curl is usually available to any user in a typical Linux system.

In this case, CURL comes to your rescue. Did you know that Curl supports telnet commands as well?

Curl is known as a tool to test HTTP layer functions. Whereas Telnet supports lower TCP level connections.

With Curl supporting telnet, it can also be used for testing the TCP connections.

eg:

curl -v telnet://www.google.com:80

-v switch is being used to spill verbose output from the request.

In this example, I've used port 80, but since it is capable of using TCP, it can use any port.

Comments

VLC skins

It's been a while from my first blog post, so today I thought to make a blog post about skins in VLC player. I think you all are familiar with VLC player if not, here's the link for the website www.videolan.org/vlc/index.htm l In brief, VLC player is a free and opensource player that can play almost all the types of media formats. Even though it is a such a nice player, it looks kind of old and rusty, like the windows classic look. But you can make it prettier by just adding some new skins to it. You can download skins for the player from here http://www.videolan.org/vlc/skins.php Then place the downloaded skin file (.vlt file) in the " skin " folder in the installation directory. eg:- in windows: C:\Program Files\VideoLAN\VLC\skins or in linux systems: ~/.local/share/vlc/skins Then, open the VLC player and go to the preferences. ...

Java, how to create a list with a single element

I wanted to create a Java List with a single element. Yet, I wanted to add more elements later. So, I was looking for a couple of ways to do this. So far there are multiple elegant ways to create a list with a single element with a one-liner. Not so much for a modifiable list though. Here's what I gathered so far. Followings are a few ways of creating a list with strictly a single entry. Can't add more elements. 1. Collections.singletonList() This returns an immutable list that cannot be modified or add more elements. // An immutable list containing only the specified object. List<String> oneEntryList = Collections. singletonList ( "one" ) ; oneEntryList.add( "two" ) ; // throws UnsupportedOperationException 2. Arrays.asList() This returns a fixed-size list consisting of the number of elements provided as arguments. The number of elements provided would be an array hence the size is fixed to the length of the array. // Returns a fixed-size list List...

Ubuntu DNS issue fix DNS_PROBE_FINISHED_BAD_CONFIG

Issue I've been playing with a VPN and somehow it messed up my DNS resolution configurations. Chrome gives DNS_PROBE_FINISHED_BAD_CONFIG error and can't ping google. So it seemed to be an issue with the DNS. Of course, restarting didn't fix it. I tried DNS lookup which gave me below. To make sure this is somehting to do with my DNS confgis, I ran the same by providing the google DNS servers. It works, which means my default DNS is not working for some reason. To make sure this, ran the below command. systemd-resolve --status Output has an entry for DNS Servers, which was ::1 Fix 1. Edit the file /etc/systemd/resolved.conf. sudo vi /etc/systemd/resolved.conf 2. Add new DNS entries. I added 2 google DNS and the cloudflare DNS sever. [Resolve] DNS=8.8.8.8 8.8.4.4 1.1.1.1 3. Restart the systemd-resolved and check the configuration is persisted in /run/systemd/resolve/resolv.conf file. sudo service systemd-resolved restart cat /run/systemd/resolve/resolv.co...

TJ is Blogging!

Search This Blog