I have been playing with SSH local and remote port forwarding and have a little understanding of it. I am wondering if it is same as SOCKS protocol and how using SSH dynamic port we can achieve it.

Also, I am wondering what is the use case of SOCKS when we have VPN and port forwarding.

Thanks in Advance

Hello, so I've been trying to fiddle with iptables for my web server. Everything is working except for passive ftp and I can't seem to get it right.

Here are my iptables rules:

-A INPUT -i lo -j ACCEPT 
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT 
-A INPUT -p tcp -m tcp --dport 22 -m state --state NEW,ESTABLISHED -j ACCEPT 
-A INPUT -p tcp -m tcp --dport 80 -m state --state NEW,ESTABLISHED -j ACCEPT 
-A INPUT -p tcp -m tcp --dport 443 -m state --state NEW,ESTABLISHED -j ACCEPT 
-A INPUT -p tcp -m tcp --dport 21 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT 
-A INPUT -p tcp -m tcp --dport 20 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT 
-A INPUT -p tcp -m tcp --sport 1024:65535 --dport 1024:65535 -m conntrack --ctstate ESTABLISHED -j ACCEPT 
-A INPUT -j DROP 
COMMIT

Select all Open in new window

I have the line IPTABLES_MODULES="nf_conntrack_ftp" in iptables-config

Anyway, all ftp users aren't able to connect (they are if I disable iptables).
To put it better, they do connect but then they can never reach their root directory and they get an error saying the / directory couldn't be found.

So there must be something wrong in my IPTABLES, but I can't find it for the life of me. I've followed every guide I found and I can't find my mistake.

Can you guys lend a hand?

vboxclient not starting in my ubuntu

To allow internet access to the internet I configured a gateway server on my small network of around 30 VMs. The gateway works well but I just want to make sure that this gateway server is as secure as possible since this gateway server is the only server in my network that has direct access to the internet. What security measures should I configure on this gateway server? Should I install a firewall? If so, how do I configure this firewall?

I have a laptop that gets connected to the internet through WiFi. but many WiFi’s and depends where I am (home,office, customer,etc...)
my laptop is windows 10 Pro.
I have a virtual box installed and I have installed on it Ubuntu.
unfortunately I am not being able to make my Ubuntu VM connect to the internet.
can someone help me on how to achieve this ?
the weird thing is that I also have another VM that is windows 2012 server and this VM has internet without me doing any configuration change !
thank you

How to best prep a new machine for running LXD containers?

I'm new to both Corosync and Pacemaker. I've looked through the documentation, and some tutorials - but I'm not sure my need is discussed. I have worked with other HA packages, so I'm familiar with most of the concepts.

In all of the tutorials, they discuss setting up a "floating IP" which is an IP address (apparently associated with a service), that is assigned automagically by Pacemaker/Corosync when the service needs to be failed over to another node.  

However, in my environment, I can't use a floating IP address, specifically. ALL of the IP addresses, to ALL computers (including my servers) are assigned by DHCP based on MAC address. The MAC-to-IP association is made via a DNS adm tool (that I do have access to.)

How I have managed failover of this sort in the past is to create virtual NICs on both machines (so BOTH machines each have two VNICs, which have the same MAC addresses). Then, if I "ifconfig up" and/or "ifconfig down" the VNICs, I defacto control which server holds the IP address.

For example:

Node 1:
# ip link add link enp2s0 address 00:11:11:11:11:11 enp2s0.1 type macvlan
# ip link add link enp2s0 address 00:11:11:11:11:01 enp2s0.2 type macvlan
# ifconfig enp2s0.1 up
# ifconfig enp2s0.2 down
# dhclient -v enp2s0.1 # obtains IP 14x.xxx.xxx.001

Node 2:
# ip link add link eno1 address 00:11:11:11:11:11 eno1.1 type macvlan
# ip link add link eno1 address 00:11:11:11:11:01 eno1.2 type macvlan
# ifconfig 

Select all Open in new window

…

Hi Network Gurus,

I'm running a Linux lubuntu running PPTP VPN Server (PoPToP version 1.4.0).  I can connect externally to the VPN server however I can't browse the local network, nor browse the internet.

(I know PPTP isn't secure but i'll address that another time)

What routes do I need to add to be able to browse the local network and internet when connected to VPN?

Network Gateway is 192.168.178.1

VPN Server is 192.168.178.58

VPN is setup as server 192.168.0.1 with client addresses as 192.168.1.* (i'm assuming subnet 255.255.0.0?)

Thanks for your help and please ask if you need more info

Cheers,
Rob

Adding User to Ubuntu

I need a user that I can use when I do not want to risk doing damage to my Ubuntu installation.

So, I ran

sudo su

then ran

adduser curiouswebster

following these instructions,
https://www.digitalocean.com/community/tutorials/initial-server-setup-with-ubuntu-18-04

is ran
usermod -aG sudo curiouswebster

but doesn't this add root privileges for curiouswebster??

If so, please help me downgrade the permissions.

I was hoping to log in as curiouswebster and install various systems, like Apache, MySQL, PHP and WordPress.

Shouldn't I use root for this?

Also, how do I log in as curiouswebster?

Thanks

I am trying to mount drives using autofs. There are 3 directories that I want to mount: home, data, and web. The mount for /home works but data and web don't work. When I mounted /data and /web manually, the shares showed up. Below has the log:
Jun 10 11:09:18 testdaviddo13 automount: Starting automounter version 5.0.7-99.el7, master map auto.master
Jun 10 11:09:18 testdaviddo13 automount: using kernel protocol version 5.02
Jun 10 11:09:18 testdaviddo13 automount: lookup_nss_read_master: reading master files auto.master
Jun 10 11:09:18 testdaviddo13 automount: do_init: parse(sun): init gathered global options: (null)
Jun 10 11:09:18 testdaviddo13 automount: spawn_mount: mtab link detected, passing -n to mount
Jun 10 11:09:18 testdaviddo13 automount: spawn_umount: mtab link detected, passing -n to mount
Jun 10 11:09:18 testdaviddo13 automount: lookup_read_master: lookup(file): read entry /home
Jun 10 11:09:18 testdaviddo13 automount: lookup_read_master: lookup(file): read entry /web
Jun 10 11:09:18 testdaviddo13 automount: lookup_read_master: lookup(file): read entry /data
Jun 10 11:09:18 testdaviddo13 automount: lookup_read_master: lookup(file): read entry /misc
Jun 10 11:09:18 testdaviddo13 automount: lookup_read_master: lookup(file): read entry /-
Jun 10 11:09:18 testdaviddo13 automount: lookup_read_master: lookup(file): read entry +auto.master
Jun 10 11:09:18 testdaviddo13 automount: lookup_nss_read_master: reading master files auto.master
Jun 10 11:09:18 …

I have executed the following command on a red hat Linux server

rpm -qa --last 

Select all Open in new window

to try and determine when the latest updates/patches were applied to the server. I ran this under the context of a non root account but still got some output.

A couple of questions:
--will the output of this command be full/accurate if it was executed under the context of a none root account.
---Secondly, how often are updates issued for red hat Linux, and are they cumulative / is it similar to Microsoft patch releases, and do the updates also cover security vulnerabilities. The last updates listed in the output of command were 2017 which raises some concerns that security bugs have not been patched, and therefore the server is vulnerable.
----Finally, does red hat Linux have a support lifecycle where they only continue to issue patches for certain versions, and if so where can I see where the version currently operated sits in this support lifecycle, e.g. is it still eligible for updates for new bugs/vulnerabilities.

I have been running Ubuntu 14 with custom tcp tuning parameters for a couple years.  I applied, via puppet, all of the same tuning parameters, but on Ubuntu 18, my TCP Time Wait is very high.  What is the best method of finding the source of this high TCP Time Wait?  The process that is using the tcp connections is a java application.

Please let me know any other information I should provide.

Graph on the left is Ubuntu 18.04, right is Ubuntu 14.04

Thank you,

Reade
tcp-time-wait.png