Memcached: cannot connect to server with libmemcached but telnet works - memcached

I have a program that is using libmemcached client in c. When working with localhost (server on same machine than client) everything works fine. When trying to run the server and client on different machines, the client cannot connect to it. I get the error message: "SERVER HAS FAILED AND IS DISABLED UNTIL TIMED RETRY".
However, when connecting through telnet (telnet ip port) the client machine can connect to the server (even when they are not the same machine). Both machines are on the same network so I am using interface eth0. Pinging works fine.

Related

psql with source IP anchoring

I am using PostgreSQL flexible server by MSAzure.
The server is not setting any connection restriction and allows connections from all IPs.
I can access to the server with psql command normally.
psql "host=.postgres.database.azure.com port=5432 dbname=postgres user=myadmin password= sslmode=require"
However, with the Source IP anchoring function by Zscaler Internet Access, it fails.
psql: server closed the connection unexpectedly This probably means the server terminated abnormally before or while processing the request.
I could not find the error logs from server side.
Also I checked the packet and it seems the server sends RST packet as soon as it received connection request message from client.
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Source IP Anchoring(SIPA) is a function which fixes source IP by transferring the packet to the proxy cloud, and from proxy cloud to private VM. The VM takes over the connection to the destination server.
Client <-> Proxy Cloud <-> VM <-> sql server
So from client side, it looks like the client is connecting to the proxy cloud.
And from sql server, it seems the server is connecting to VM.
The VM only performs outbound connection and never allows inbound connection.
This means connection pushed from server to client is not supported (like P2P, Application lelvel gateway, SIP, RTSP, Bittorent).
Does Postgresql connection requires inbound connection from server to client?
I tried disabling SSL connection, but the result was same.
The client version and server version are both same.
Also I tried connecting from pgAdmin 4, but failed again.
I'll appreciate any clue on this.

PostgreSQL SSH port forwarding via Windows/PuTTY

I have PostgreSQL 9.4 running on a Linux VPS, and I need to be able to connect to it over SSH from both Linux and Windows clients. (I will later need to connect to multiple servers, and so that all clients use the same port numbers, I'm forwarding to port 5551 for the first server, then I will use 5552, 5553, etc.)
From a Linux client I just run ssh -fNg -L 5551:localhost:5432 user#remote1.com and connect to localhost:5551 with PGAdmin3 or any other client app. Works great.
On Windows, I'm using PuTTY and Pageant. I got the connection to user#remote1.com via terminal working, then I went to the SSH Tunnels and added L5432 localhost:5551. Terminal connection still works, but when I try to connect with PGAdmin3 to localhost:5551 I get an error:
could not connect to server: Connection refused (0x0000274AD/10061) Is the server running on host "localhost" (::1) and accepting TCP/IP connections on port 5551?
I resolved it. Like many things, this is obvious in hindsight. I had things backward in the SSH Tunnels setup in PuTTY. It needs to be L5551 remote1.com:5432

Can't create sockets to domain

I'm running ubuntu 10.04 lts on my server.
I ran into a problem where my server.jar file couldn't create an SSL socket to prod.euw1.lol.riotgames.com.
I tried "telnet prod.euw1.lol.riotgames.com 2099", but it can't establish a connection.
However, "telnet prod.euw1.lol.riotgames.com 2099" runs fine on a different ubuntu 12.xx server that I ssh'd into, and it works fine on my personal computer.
And strangely, connections to other host servers with "telnet prod.na1.lol.riotgames.com 2099" or "telnet prod.eun1.lol.riotgames.com 2099" on my ubuntu 10.04 machine work just fine.
I don't know what steps to take next, I've already flushed my iptables rules to accept all incoming/outgoing traffic, and the IP address that the domain resolves to is the same across all of the computers I've tried.

EC2 Internal Sockets

I'm trying to have two process communicate through a socket connection. One of these is a python app, and the other is a php script.
I've created and tested the client/server combination on my home computer and it functions properly. However, when I deploy onto an EC2 instance (ubuntu 10.10 64bit ami + apache + php) I get an unable to connect to socket error (111 Connection Refused) from the php script. The python app is able to bind to the socket and listen to messages but the php script is unable to send messages.
I've opened the required ports in the amazon security group and I can connect to the port externally using telnet. However if I attempt to connect with telnet from within the server I get the same connection refused error.
How can I solve this issue?
Edit: Both processes are on the same instance
The issue had nothing to do with EC2 explicitly. I was not binding to localhost, but instead binding to my hostname. On a local network that was the same as my localhost ip, however on ec2 it was not. Switching to binding to localhost fixed the issue.

phing FtpDeploy "connection to host failed"

I'm getting the following error when trying to deploy a ZIP file to a remote FTP server. I tried connecting to the server using an FTP client (filezilla) and all goes well.
Also, when connecting to a public ftp like ftp.belnet.be connections work fine.
I'm trying to send the file to a VSFTPD server behind a router using port forwarding. Again, this works fine from any location using Filezilla, phing is not connecting though...
BUILD FAILED
/deployment/build.xml:60:12: Could not connect to FTP server x.x.x.x on port 21: Connection to host failed
Total time: 2 minutes 30.09 seconds
this was a firewall issue that has been resolved.