The sys admin’s daily grind: sslh


Article from Issue 111/2010

Some of Charly’s servers run the SSH daemon on port 443 rather than on the standard port 22. If an SSL-capable Apache web server starts causing trouble, his method of settling the dispute is sslh.

Whether I happen to be in an Internet café, using the wireless LAN at a hotel, or using a public hotspot at an airport, I continually find myself locked up behind a firewall that refuses connections to target port 22. Of course, any firewall will generously let traffic to ports 80 and 443 pass.

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