Cfrtjryk

I've downloaded CentOS 7 Minimal and installed on an old laptop. I want to be able to ssh to the machine from other machines on the same lan. But I keep getting this error ..

ssh: connect to host 192.168.0.17 port 2110: No route to host

192.168.0.17 .. Is the new CentOS machine.

rob@ciserver:~$ hostname

ciserver

192.168.0.11 .. Is the machine I'm trying to access from.

rob@work:~$ ifconfig | grep "inet addr" | tail -1

          inet addr:192.168.0.11  Bcast:192.168.0.255  Mask:255.255.255.0

rob@work:~$ ping -vvv 192.168.0.17

PING 192.168.0.17 (192.168.0.17) 56(84) bytes of data.

From 192.168.0.11 icmp_seq=1 Destination Host Unreachable

These are the config steps and info from my CentOS install, hopefully someone can help identify when I cannot remotely access the machine?

rob@ciserver:~$ ip addr

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN

  link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

  inet 127.0.0.1/8 scope host lo

    valid_lft forever preferred_lft forever

  inet6 ::1/128 scope host

    valid_lft forever preferred_lft forever

2: enp14s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN qlen 1000

  link/ether xx:xx:xx:xx:xx:xx brd xx:xx:xx:xx:xx:xx

3: wlp20s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000

  link/ether xx:xx:xx:xx:xx:xx brd xx:xx:xx:xx:xx:xx

  inet 192.168.0.17/24 brd 192.168.0.255 scope global dynamic wlp20s0

    valid_lft 84703sec preferred_lft 84703sec

  inet6 xxxx::xxxx:xxxx:xxxx:xxxx/xx scope link

    valid_lft forever preferred_lft forever

I modified my ssh config to listen on a different port and not allow root access ..

rob@ciserver:~$ grep Port /etc/ssh/sshd_config 

Port 2110

rob@ciserver:~$ grep Root /etc/ssh/sshd_config 

PermitRootLogin no

rob@ciserver:~$ sudo systemctl reload sshd.service

rob@ciserver:~$ sudo service sshd restart

I added a new rule to firewall for updated ssh port ..

sudo firewall-cmd --permanent --remove-service=ssh

sudo firewall-cmd --permanent --add-port=2110/tcp

sudo firewall-cmd --reload

sudo systemctl enable firewalld

/etc/hosts contents ..

127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain6

::1 localhost localhost.localdomain localhost4 localhost4.localdomain6

I think by default selinux is enabled and is only configured to allow port 22 for ssh. have you either disabled it or added an exception for the new port?

semanage port -a -t ssh_port_t -p tcp 2110

I am a necromancer, but if this should save some other poor soul the trouble:

In nmcli setup, I had applied the wrong subnet mask.

nmcli con add type ethernet con-name $CONNAME ifname $IFNAME 

    ip4 192.168.1.20 gw4 192.168.1.1

...gave me a mask of 255.255.255.255, with a brd (broadcast) equal to the server's IP. That server wasn't going to be talking to anyone.

The proper setup (this is minimal install, so it's important) would be

nmcli con add type ethernet con-name $CONNAME ifname $IFNAME 

    ip4 192.168.1.20/24 gw4 192.168.1.1

Of course, check the CIDR prefix of your subnet mask for your own network. But this solved the problem for me.

as root:

-A INPUT -m state --state NEW -m tcp -p tcp --dport 2110 -j ACCEPT

restart ssh service checks the ssh connection, or restart the system.