I am trying to ssh into my server at work (CentOS) from my laptop (Ubuntu). When I am at home, I do it by running the following script on the server (I start it while I am physically at work):
ssh -R (port #):localhost:22 (name@home ip)
I do this because it doesn't accept connections from external IPs. Then, I can ssh into the specified port on my laptop, and it works fine.
However, when I am actually at work, I cant ssh to the server. The other people in my office can. They do this very simple command (only works while they are at work, since they need an IP from inside the system):
ssh (username)@(work ip)
And they are automatically logged in. When I do that, I get no response; no public key denial, no wrong username, no response at all. Eventually it times out. But I know the server has ssh running, because everyone else can do it.
Additionally, if I do this on my laptop, while at work:
ping (work ip)
I do get response packets, with no loss, almost no lag. But ssh doesn't work.
I can ssh to other places from my laptop, both while I am at home and at work. So my laptop is properly configured to ssh to things, it just doesn't reach the work server for some reason. I talked to the guy who set it up and he insists there is no whitelist; the only security from internal IPs (and I am physically on site, so I have an internal IP, so there should be no need to do the ssh -r like I do at home) is the private/public RSA key system, and I know the keys must be already set up, because it works when I do the ssh -R from home. Plus, if the keys were not set up, I would get a public key denial, instead of no response at all, right?
If I do ssh -vv, this is the last line before it times out:
debug1: Connecting to ccny6 [WORK IP] port 22.
I see other people have posted similar questions, but the responses they seem to generally be "is the server running the ssh service" etc, which I know it is as other people can ssh to do (as can I if I'm using the ssh -r tunnel), so none of those responses did me much good, unfortunately.
Summary: I can ssh to a server from OFF site via a ssh tunnel, but can't ssh to it while I am right next to it using direct ssh, even though I can ping it, and others can ssh to it.