|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
[ More Info ]
netstat -a | grep ssh. If you
are returned to the shell prompt with no results displayed, then the
system isn't listening for SSH connections on port 22.
root@Microknoppix:/# netstat -a | grep ssh root@Microknoppix:/#
You can also check to see if it is running by using the command
service --status-all. If there is a plus sign next to
ssh, it is running. If, instead, there is a minus sign, it is not
running.
root@Microknoppix:/# service --status-all [ - ] acpid [ - ] bootlogd [ - ] bootlogs [ ? ] bootmisc.sh [ ? ] checkfs.sh [ - ] checkroot.sh [ ? ] console-screen.sh [ ? ] console-setup [ ? ] cpufrequtils [ ? ] cron [ ? ] cryptdisks [ ? ] cryptdisks-early [ + ] dbus [ + ] ebtables [ ? ] etc-setserial [ - ] fsaua [ ? ] fsrcdtest [ - ] fsupdate [ ? ] fsusbstorage [ ? ] gpm [ ? ] hdparm [ - ] hostname.sh [ ? ] hwclock.sh [ ? ] hwclockfirst.sh [ ? ] ifupdown [ ? ] ifupdown-clean [ ? ] kexec [ ? ] kexec-load [ ? ] keyboard-setup [ ? ] keymap.sh [ ? ] killprocs [ ? ] klogd [ ? ] knoppix-autoconfig [ ? ] knoppix-halt [ ? ] knoppix-reboot [ ? ] knoppix-startx [ ? ] loadcpufreq [ ? ] lvm2 [ ? ] mdadm [ ? ] mdadm-raid [ ? ] module-init-tools [ ? ] mountall-bootclean.sh [ ? ] mountall.sh [ ? ] mountdevsubfs.sh [ ? ] mountkernfs.sh [ ? ] mountnfs-bootclean.sh [ ? ] mountnfs.sh [ ? ] mountoverflowtmp [ ? ] mtab.sh [ + ] network-manager [ ? ] networking [ - ] nfs-common [ - ] nfs-kernel-server [ + ] open-iscsi [ - ] portmap [ ? ] pppstatus [ ? ] procps [ ? ] rc.local [ - ] rmnologin [ - ] rsync [ ? ] screen-cleanup [ ? ] sendsigs [ ? ] setserial [ - ] smartmontools [ - ] ssh [ - ] stop-bootlogd [ - ] stop-bootlogd-single [ ? ] sudo [ ? ] sysklogd [ ? ] udev [ ? ] udev-mtab [ ? ] umountfs [ ? ] umountiscsi.sh [ ? ] umountnfs.sh [ ? ] umountroot [ - ] urandom
On a Microknoppix system, such as may be present on a Rescue CD or
other live CD or
DVD, the SSH server software may not even be present on the CD or DVD. You
can use the apt-cache search command followed by a
regular
expression, in this case ssh, to determine if
the package is present on the system.
root@Microknoppix:/# apt-cache search ssh libssl0.9.8 - SSL shared libraries sshstart-knoppix - Starts SSH and sets a password for the knoppix user openssh-client - secure shell (SSH) client, for secure access to remote machines
In the case above, I can see that only an SSH client is present. If I run the
sshstart-knoppix command, I will be prompted to set a password for the
knoppix account on the system, but, since the SSH server package is not present,
the command won't actually start an sshd service.
If the SSH server service is not running and the SSH server package
is not installed, first you need to install
the SSH server software. To do so you may need to add an appropriate
package repository, such as http://us.debian.org/debian to
the file /etc/apt/sources.list. E.g., you will need to do
so when using the
F-Secure 3.16
Rescue CD.
If you attempt to install the openssh-server package and
see the results below, then you need to add an appropriate repository
to /etc/apt/sources.list so the system can find the package
and download it.
root@Microknoppix:/# apt-get install openssh-server Reading package lists... Done Building dependency tree... Reading state information... Done Package openssh-server is not available, but is referred to by another package. This may mean that the package is missiong, has been obsoleted, or is only available from another source E: Package 'openssh-server' has no installation candiate root@Microknoppix:/#
You can add the http://us.debian.org/debian repository
to the end of the file by using the cat command. Type
cat >> /etc/apt/sources.list (make sure you use two
greater than signs so as to append to the file rather than overwrite it)
then type deb http://http.us.debian.org/debian stable main contrib
non-free and then hit Enter. Then hit the Ctrl
and D keys simultaneously, i.e., Ctrl-D. Next issue the
command apt-get update. When that command has completed,
issue the command apt-get install openssh-server. When
informed of the amount of additional disk space that will be needed and
them prompted as to whether you wish to continue, type "Y". When
prompted "Install these packages without verification [y/N]?",
enter "y".
When the command completes you can then issue the command
netstat -a | grep ssh to verify that the system
is listening on the SSH port, which is normally TCP port 22.
root@Microknoppix:/# netstat -a | grep ssh tcp 0 0 *:ssh *:* LISTEN tcp6 0 0 [::]:ssh [::]:* LISTEN
If you issued the command apt-cache search openssh-server
at this point, you would see the following:
root@Microknoppix:/# apt-cache search openssh-server openssh-server - secure shell (SSH) server, for secure access from remote machines
Use the passwd command to set the password for
the knoppix account, which you can use for remote logins.
root@Microknoppix:/tmp# passwd knoppix Enter new UNIX password: Retype new UNIX password: passwd: password updated successfully Hit Return to continue.
Once the SSH server service is running, you should be able to
connect to the system remotely with an SSH client on another system.
To determine what IP address you should use for the connection, you
can issue the command ifconfig. You should see
an inet addr line that will provide the system's
current IP address. It will typically be in the information
provided for the eth0 network interface. The
l0 interface is the
local loopback interface, which will have an IP address
of 127.0.0.1. You can use that address to verify
that the SSH connectivity is working from the local system,
but not for a remote login.
root@Microknoppix:/# ifconfig
eth0 Link encap:Ethernet HWaddr 00:18:f3:a6:01:8a
inet addr:192.168.0.40 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: fe80::218:f3ff:fea6:18a/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:334286 errors:0 dropped:0 overruns:0 frame:0
TX packets:262393 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:289663552 (276.2 MiB) TX bytes:183570787 (175.0 MiB)
Interrupt:23 Base address:0xc000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:24 errors:0 dropped:0 overruns:0 frame:0
TX packets:24 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2331 (2.2 KiB) TX bytes:2331 (2.2 KiB)To login remotely via SSH, use knoppix for the login
account and provide the password you entered above for that account
when prompted for the password. Once you have logged in under the
knoppix account, you can obtain a Bash shell prompt
for the root account using the command sudo bash.
knoppix@Microknoppix:~$ sudo bash
root@Microknoppix:/home/knoppix#If you then need to stop, start, or restart the service, you can do
so using /etc/init.d/ssh followed by the appropriate parameter.
root@Microknoppix:/# /etc/init.d/ssh
[info] Usage: /etc/init.d/ssh {start|stop|reload|force-reload|restart|try-restar
t|status}.The configuration file for the SSHD service is
/etc/ssh/ssh_config. You can change values by removing the
comment character, #, from the beginning of a line and chaning the
default value on the line, then stopping and restaring the service. Note:
stopping the sshd service won't disconnect an existing SSH connection, so
you can remotely restart the service with
/etc/init.d/ssh restart without being disconnected.
