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Questions tagged [firewall]

A Firewall is an application or hardware device used to inspect and filter network traffic.

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1answer
26 views

Firewall refuse my connection to DB

We are working on software that require to connect to database on the server (Win2012)(LAN), after activating windows firewall, we couldn't connect to DB. I've set a rule for inbound and I Excluded ...
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0answers
10 views

Cockpit-project integration with firewall

I have cockpit-project on my VPS (running on Ubuntu 18.04). But still trying to figure out how to integrate it with firewalld. I have uninstalled ufw and installed firewalld, but firewall section in ...
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13 views

Fail2Ban with Kubernetes? or any other alternative? [on hold]

-1 down vote favorite I am looking for some tools can auto detect brute-forcing user, and block / make log file itself to notice Sysadmin. I know Fail2Ban can do this kinda job on legacy environment, ...
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1answer
18 views

cannot open port 8000 in google compute instance

Check one - Application is running or not port 8000 in the GCP instance kranthi@xxx-dev-xxx:~$ netstat -tlpn | grep 8000 (Not all processes could be identified, non-owned process info will not be ...
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0answers
20 views

Windows Server 2008 - Strange Network Connectivity (Firewall)

So we had a network outage last week for a few hours and it caused windows server 2008 r2 to be showing 'no internet' with a yellow exclamation mark. The server has 2 interfaces (on same network), ...
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1answer
29 views

In which direction to open AD Connect ports?

Practising setting up SSPR in my Azure lab and struggling with which ports to open on the AD Connect server. I've found the list of firewall ports to open on Microsoft docs but as a beginner I'm not ...
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1answer
16 views

UFW comment existing rule?

I'm trying to comment an existing ufw firewall rule, but i can't find the exact command I can easily add a rule with comment like sudo ufw allow in on eth0 to any port 80 comment 'test' but how i ...
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3answers
41 views

Unable to RDP to VM hosted in Windows 2016 Server

I have a windows 2016 server, which hosts a VM (Oracle Virtual Box). VM network setting is NAT with port forward. e.g. 192.168.10.17:5001 gets forward to 10.0.2.15:3389 Here are steps I have tried: ...
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15 views

config iptables rules for pptp vpn

I used Setup PPTP VPN Server on CentOS 6 guid to setup pptp vpn on my server. Every things is fine and vpn work without csf and iptables. But when i enable csf / iptables i can't connect to vpn ...
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3answers
58 views

Test if UFW firewall change would prevent me from reconnecting

I want to manage UFW firewall rules on a number of remote Ubuntu 18.04 machines using Ansible. If a change to the firewall rules prevents me from re-connecting to the machines via SSH that would be ...
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1answer
35 views

OpenVPN is not connecting to services behind it (iptables?)

After connection to openvpn i can not ping even vpn address (172.16.0.1) here is my vpn config: ##protocol port port 1194 proto tcp dev tun ##ip server client server 172.16.0.0 255.255.0.0 ##...
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17 views

GCP/GCE / Docker / GitLab - gitlab_shell_ssh_port - Connection timed out

I'm following GitLab Docker images | GitLab and even though gitlab container appears to be healthy: # docker-compose ps Name Command State Ports ...
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2answers
212 views

Does it makes sense to configure iptables when you have configured AWS EC2 security groups?

We are using some Amazon EC2 instances with configured Security Groups (e.g. can SSH only from particular IPs -- sorry I cant post rules). Some time ago I checked iptables and it looked like there ...
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2answers
16 views

How to update an ipset name-based entry

I need to handle on my firewall (Firehol, which is then transformed into iptables) a few dynamic entries. In an ideal world I would use a name (instead of an IP address) which always points to the ...
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1answer
56 views

How to manage an inaccessible remote windows server

I have a Windows server that hosts my applications. The server in question is managed by a third party company. This server is accessible by remote desktop from a jump box. During the configuration ...
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1answer
191 views

CentOS 7 SNMP port always closed

I have a CentOS 7 server in which I opened up ports for SNMP connections. Even though I can see the ports open here: [matias@Centos_7_VM ~]$ sudo firewall-cmd --list-all [sudo] password for matias: ...
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0answers
18 views

Tcpdump receives packets but they are not delivered to firewall

I am working with Proxmox, OpenVPN and Mikrotik Router. When I try to connect from OpenVPN client (192.168.10.13) to VM (192.168.1.19) hosted on Proxmox I don't get any response. Proxmox host (192....
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0answers
12 views

ASA same-security level (or now) and access lists

On ASA I got two interfaces with same security LAN, and LAN2. I want only specific traffic to pass from LAN to LAN2. Let say that I want to pass 10.0.0.0/12 but block 172.16/12. How to achive this? ...
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1answer
28 views

Windows Server 2012 r2 firewall settings for FTP in active mode

I have created an FTP site in Windows Server 2012 R2. The server is hosted on a domain and the user is also on a domain. The FTP is configured on some random port 3586 and will work on Active Mode. ...
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1answer
51 views

Configuring correct firewall settings for GCP HTTP load balancer

I have two VMs running HTTP servers on port 8545 as shown in the figure and placed in an instance group. I created a HTTP load balancer in GCP to balance HTTP requests from end users. However, with ...
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0answers
19 views

DNS resolve delays with Watchguard M370 routers when single-request is disabled

After replacing our Watchguartd M200 router with a new Watchguard M370 router, we experienced delays in DNS resolving from linux clients, when packages to the DNS server are rooted via the Firewall. ...
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0answers
12 views

Simple SuSEfirewall2 config

I'm trying to set up what I feel like is a very simple SuSEfirewall2 config on a SLES 11SP4 VM with a single interface: Goals: Allow 80,443,icmp from any IP Allow 22 from 10.120.0.0/16 Allow all ...
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2answers
61 views

Working with port 443 only and blocking port 80

We're trying to harden firewall settings for a computer. We allowed only port HTTPS (443), NTP (123) and DNS (53). Now we fail to send POST requests to a web api application unless we open port 80. ...
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1answer
36 views

Multiple Asterisk Servers Behind Single NAT

I'm debugging an issue we're having with VoIP SIP registration. After looking at packet dumps, I think the issue results from 2 subnets accessing the same web service and the router not knowing how to ...
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0answers
21 views

Userbased Bandwidth limiting on Cyberoam CR35iNG

I want to limit the bandwidth of each "user" on my Cyberroam firewall. This normally works with QoS, but the problem here is, that my users aren't logged into the firewall, which (afaik) needs to be ...
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0answers
32 views

Palo Alto firewall does not display traffic log

I've just installed Palo Alto firewall VM version in virtual box. I was able to access it via WEB (https) and SSH. However, when I check traffic log it was empty. I generated a few traffic such as ...
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1answer
82 views

Active Directory is being attacked remotely

Thanks for clicking, I'm having an issue with our server where our Active Directory is being abused by random external servers. From what I can gather, our server is the victim of an LDAP forwarding ...
0
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1answer
29 views

Postfix: Blocking connections on submission port based on geoip

Currently I'm reducing failed authentication spam in logs by blocking access to Dovecot and SSHD based on the IP address country of origin. Both services require authentication and I have no users or ...
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2answers
59 views

Docker networking setup that is private and proxied

Above is a layout of the desired network. I am struggling with getting it just right. The internal link from the router is not relevant for this problem. Requirements: The only container directly ...
2
votes
1answer
47 views

Group Policy setting to activate Windows Firewall when not on Business Domain

I've been trying to figure out GPO settings for a couple of days and cannot figure out how to apply a filter of some sort to Windows Firewall to turn it ON when any employee is not on the domain (10.0....
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0answers
35 views

Hosting a virtual machine in Russia

One of the web-hosted projects I work on is being blocked in Russia (ostensibly due to Russia's attempt at blocking a certain messaging service.) The service must be accessible by ephemeral/mobile ...
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0answers
23 views

Configuring a Zimbra server what port to open on the perimetral firewall for outgoing traffic?

I've got credential to access a server where i need to install zimbra server, prior to that I've asked to have this incoming port opened on the perimetral firewall of the isp: https://wiki.zimbra.com/...
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1answer
105 views

Windows Firewall: Apply local firewall rules

I have an environment where we have a GPO which we have set on all profiles to have the setting: Apply local firewall rules: No I've confirmed that the GP is applied successfully by using gpresult/...
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1answer
87 views

How to block IPs that cause excessive 404 errors with Fail2ban?

I have installed Fail2Ban v0.10.2 on Ubuntu 18.04 with Apache 2.4.29 and enabled the standard ssh and apache jails for basic protection with email notification warnings, when an IP is blocked. Having ...
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1answer
127 views

iptables rules for blocking internet but allow local network for devices

I'm trying to block access to the internet for certain devices on my network. DD-WRT has a way to do it but only those that are on WAN. The device is connected on LAN. What would be the iptables rules ...
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2answers
107 views

delete a table in iptables

how do I delete a table in iptables (as opposed to a chain)? I have some empty tables that are getting output by iptables-save even though I'm only using the 'filter' table. For example, I'd like ...
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0answers
51 views

Do not clear NAT table when using Shorewall

I am using shorewall in my system, although I do not want to implement NAT rules through this. NAT rules are programmed separately using iptables command. So now, suppose I created some filtering ...
0
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1answer
916 views

ASA Can ping between subnets, but not pass IP traffic (access rules in place, security levels ok)

I have tried getting my ASA to route traffic between subnets, i got it working for 10 minutes but after some changes (unfortunately not an ASA expert) i have broken something. One example is 192.168....
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1answer
43 views

Postfix do not listen on SMTP Ports

i have a problem with my Postfix on Ubuntu 18.04. Problem seems to be Postfix do not listen on SMTP Ports 25, 465 or 587. UFW firewall is disabled. Telnet result to the machine on Ports 25,465 and ...
0
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1answer
29 views

Services running on same host as OpenVPN do not receive traffic from VPN

So we are setting up and testing new internal systems, using Docker to deploy OpenVPN, Jenkins, and bind all on the same host. We want to restrict access to only come from traffic that originates from ...
0
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1answer
28 views

iptables - can't route between VPN and LAN

I'm using the docker image hwdsl2/ipsec-vpn-server as my VPN server and have managed to successfully establish a connection between a remote site and this site. Site overview: Site 1: Using hwdsl2/...
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0answers
43 views

2 Offices, 2 Internet Connections, 1 leased line connecting the offices: How to route LAN traffic?

We have 2 offices, each with their own internet connection. We also have a leased line/LAN extension provided by the ISP at each location as well. The way this works is that the ISP provided us a ...
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0answers
42 views

Connecting 2 Physical Offices, Separate Subnets, FortiGate as the Gateway for each site, leased line/LAN extension in place

I have two offices, each with their own internet connection and there's also a 'LAN Extension' or leased line connecting both of these offices (essentially 2 ports in the ISP router for each site, 1 ...
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0answers
34 views

pfSense : How to do 1:1 NAT to server hosted at remote location linked through IPSec tunnel

We have 2 data centers at 2 different locations and are moving our services from location A to B without interruption. Both location have a PFSense Firewall configured with IPSec tunnel between each ...
2
votes
3answers
118 views

Safe way to deploy iptables using ansible

I would like to deploy iptables rules in a "safe" way using ansible where for safe I think at something like the shorewall command safe-restart. So I'm looking for a workflow like this: install the ...
0
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1answer
83 views

Firewall (Firebox - WatchGuard) configuration for exchange server 2016

I have installed Exchange Server 2016 and ready to use. My provider has done relative changes to public domains. Below picture shows my network topology x.x.x.x is my static IP address What changes ...
0
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1answer
52 views

Is Yast Firewall the same as IPTables?

I am confused about Yast Firewall on OpenSuse. Is Yast a different firewall to IPTables? Or is it simply a tool used to control the firewall that is already installed on the system? Edit: Fix typos.
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1answer
16 views

Issue accessing remote web service port from a Windows Server box

I have an issue where every laptop and phone I have access to can access a 3rd party remote URL (which contains WCF service) at an address like: http://example.com:17001/ServiceName.svc This can be ...
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0answers
72 views

Redirect clients based on MAC address - OpenWRT/LEDE

on OpenWRT (LEDE) router I have the following redirection: config redirect option proto 'tcp' option target 'DNAT' option dest 'lan' option _name 'Proxy for HTTP' option src 'lan' ...
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0answers
9 views

How to verify conformity of firewall/iptables rules with actual ufw rules?

ufw is awesome for setting up firewall rules. I'm not well versed regarding iptables rules, and therefore ufw is a really helpfull. When shooting iptables -L , there are a ton of rules added and set-...