Hi! I want to change the sshd port at install for centos7 but i am not sure if i am on the good track (and it is time expensive to make many try-outs).. So, i would be grateful if someone with experience can spot if i have problems with my planning.. (the actual purpose is that after installation i have access for my ansible provisioning)
first make sure ssh is started services --enabled=sshd,chronyd
then .. i imagine that in the %post section %post --interpreter=/usr/bin/bash --log=/root/ks-post.log 1. i could use sed to change the port sed -i 's/#Port\ 22/Port 60000/' /etc/ssh/sshd_config 2. sed -i 's/#PermitRootLogin\ yes/PermitRootLogin\ yes/' /etc/ssh/sshd_config 3. enable key access mkdir -p /root/.ssh chmod 700 /root/.ssh cat << EOF >> /root/.ssh/authorized_keys my_ssh_pubkey EOF 4. semanage port -a -t ssh_port_t -p tcp 60000 5. firewall-cmd --permanent --zone=public --add-port=60000/tcp 6. systemctl enable firewalld.service
did i miss anything? Thank you! Adrian
On Wed, Feb 17, 2016 at 2:48 PM, Adrian Sevcenco Adrian.Sevcenco@cern.ch wrote:
Hi! I want to change the sshd port at install for centos7 but i am not sure if i am on the good track (and it is time expensive to make many try-outs).. So, i would be grateful if someone with experience can spot if i have problems with my planning.. (the actual purpose is that after installation i have access for my ansible provisioning)
first make sure ssh is started services --enabled=sshd,chronyd
then .. i imagine that in the %post section %post --interpreter=/usr/bin/bash --log=/root/ks-post.log
- i could use sed to change the port
sed -i 's/#Port\ 22/Port 60000/' /etc/ssh/sshd_config 2. sed -i 's/#PermitRootLogin\ yes/PermitRootLogin\ yes/' /etc/ssh/sshd_config 3. enable key access mkdir -p /root/.ssh chmod 700 /root/.ssh cat << EOF >> /root/.ssh/authorized_keys my_ssh_pubkey EOF 4. semanage port -a -t ssh_port_t -p tcp 60000 5. firewall-cmd --permanent --zone=public --add-port=60000/tcp 6. systemctl enable firewalld.service
did i miss anything?
The %post section is definitely where you want your commands. I'd combine the sed commands in points 1 and 2, but that's a small nit picky suggestion. ( You forgot to escape the space before 60000 in the first sed expression you provided. )
sed -i -e 's/#Port\ 22/Port\ 60000/' -e's/#PermitRootLogin\ yes/PermitRootLogin\ yes/' /etc/ssh/sshd_config
Though I will note there is some sort of syntax error with the PermitRootLogin sed expression (present in the original you provided). I spent a moment looking at it and the problem with that second expression evades me right now. *grumble*
On 02/18/2016 10:27 AM, Mike - st257 wrote:
( You forgot to escape the space before 60000 in the first sed expression you provided. )
True, but you shouldn't need to escape spaces at all:
sed -i 's/#Port 22/Port 60000/; s/#PermitRootLogin yes/PermitRootLogin yes/'
Though I will note there is some sort of syntax error with the PermitRootLogin sed expression (present in the original you provided). I spent a moment looking at it and the problem with that second expression evades me right now.
I ran the command he provided and didn't see a problem. What did you see?
On Thu, Feb 18, 2016 at 1:49 PM, Gordon Messmer gordon.messmer@gmail.com wrote:
On 02/18/2016 10:27 AM, Mike - st257 wrote:
( You forgot to escape the space before 60000 in the first sed expression you provided. )
True, but you shouldn't need to escape spaces at all:
Right, I notice that now. And those expressions can be combined in one string and not two expressions. ;-)
sed -i 's/#Port 22/Port 60000/; s/#PermitRootLogin yes/PermitRootLogin yes/'
Though I will note there is some sort of syntax error with the
PermitRootLogin sed expression (present in the original you provided). I spent a moment looking at it and the problem with that second expression evades me right now.
I ran the command he provided and didn't see a problem. What did you see?
I know I saw an error message yesterday, but I don't see one now (ran it without the "in place" replace option as a test). *shrugs* Now I look like I'm seeing things. :-/
Thank goodness it's Friday.
On Thu, Feb 18, 2016 at 3:48 AM, Adrian Sevcenco Adrian.Sevcenco@cern.ch wrote:
Hi! I want to change the sshd port at install for centos7 but i am not sure if i am on the good track (and it is time expensive to make many try-outs).. So, i would be grateful if someone with experience can spot if i have problems with my planning.. (the actual purpose is that after installation i have access for my ansible provisioning)
first make sure ssh is started services --enabled=sshd,chronyd
then .. i imagine that in the %post section %post --interpreter=/usr/bin/bash --log=/root/ks-post.log
- i could use sed to change the port
sed -i 's/#Port\ 22/Port 60000/' /etc/ssh/sshd_config 2. sed -i 's/#PermitRootLogin\ yes/PermitRootLogin\ yes/' /etc/ssh/sshd_config
Not sure if off topic, but you may also consider disabling password login and use key pair to connect through ssh
- enable key access
mkdir -p /root/.ssh chmod 700 /root/.ssh cat << EOF >> /root/.ssh/authorized_keys my_ssh_pubkey EOF 4. semanage port -a -t ssh_port_t -p tcp 60000 5. firewall-cmd --permanent --zone=public --add-port=60000/tcp 6. systemctl enable firewalld.service
did i miss anything? Thank you! Adrian
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