1 Dropbear for Debian 2 ------------------- 3 4 This package will attempt to listen on port 22. If the OpenSSH 5 package ("ssh") is installed, the file /etc/default/dropbear 6 will be set up so that the server does not start by default. 7 8 You can run Dropbear concurrently with OpenSSH 'sshd' by 9 modifying /etc/default/dropbear so that "NO_START" is set to 10 "0" and changing the port number that Dropbear runs on. Follow 11 the instructions in the file. 12 13 This package suggests you install the "ssh" package. This package 14 provides the "ssh" client program, as well as the "/usr/bin/scp" 15 binary you will need to be able to retrieve files from a server 16 running Dropbear via SCP. 17 18 Replacing OpenSSH "sshd" with Dropbear 19 -------------------------------------- 20 21 You will still want to have the "ssh" package installed, as it 22 provides the "ssh" and "scp" binaries. When you install this 23 package, it checks for existing OpenSSH host keys and if found, 24 converts them to the Dropbear format. 25 26 If this appears to have worked, you should be able to change over 27 by following these steps: 28 29 1. Stop the OpenSSH server 30 % /etc/init.d/ssh stop 31 2. Prevent the OpenSSH server from starting in the future 32 % touch /etc/ssh/sshd_not_to_be_run 33 3. Modify the Dropbear defaults file, set NO_START to 0 and 34 ensure DROPBEAR_PORT is set to 22. 35 % editor /etc/default/dropbear 36 4. Restart the Dropbear server. 37 % /etc/init.d/dropbear restart 38 39 See the Dropbear homepage for more information: 40 http://matt.ucc.asn.au/dropbear/dropbear.html 41 42 43 Entropy from /dev/random 44 ------------------------ 45 46 The dropbear binary package is configured at compile time to read 47 entropy from /dev/random. If /dev/random on a system blocks when 48 reading data from it, client logins may be delayed until the client 49 times out. The dropbear server writes a notice to the logs when it 50 sees /dev/random blocking. A workaround for such systems is to 51 re-compile the package with DROPBEAR_RANDOM_DEV set to /dev/urandom 52 in options.h. 53
