Search Results

Search found 3251 results on 131 pages for 'firewall'.

Page 11/131 | < Previous Page | 7 8 9 10 11 12 13 14 15 16 17 18  | Next Page >

• How to Configure Ubuntu’s Built-In Firewall

  - by Chris Hoffman

  Ubuntu includes its own firewall, known as ufw – short for “uncomplicated firewall.” Ufw is an easier-to-use frontend for the standard Linux iptables commands. You can even control ufw from a graphical interface. Ubuntu’s firewall is designed as an easy way to perform basic firewall tasks without learning iptables. It doesn’t offer all the power of the standard iptables commands, but it’s less complex. HTG Explains: Why Linux Doesn’t Need Defragmenting How to Convert News Feeds to Ebooks with Calibre How To Customize Your Wallpaper with Google Image Searches, RSS Feeds, and More

  Read the article

• Restrict RDP port based on a Dynamic DNS

  - by webnoob

  Hi All, I want to set a restriction on my firewall (windows firewall on windows 2008) to only allow connections from a certain dynamic DNS. Is this possible? The reason I ask is that this would allow us to just change the IP on the dynamic DNS if our IP changes and means we won't get locked out of RDP. This also allows me to RDP in from other locations that have IP's that are not static by just changing the IP against the DNS. Any ideas. Thanks in advance.

  Read the article

• Új adatbázis-biztonsági termék: Audit Vault and Database Firewall, lényegesen olcsóbban

  - by user645740

  Az Oracle összevonta az Audit Vault és a Database Firewall termékeket, még szélesebb felhasználói körnek elérhetové téve az adatbázisok biztonságának magasabb szintjét. Az új termék, az Oracle Audit Vault and Database Firewall (AVDF) mostantól kedvezobb áron érheto el. A jelentések megtekintéséhez restricted use-ban tartalmazza  a Business Intelligence Publisher licencet. Az adatgyujto, management szerver komponensek kiemelten védettek, az Audit Vault Server és a Database Firewall szerverekre restricted use-ban használhatók:Oracle Database Enterprise Edition, Database Vault, Partitioning, Advanced Compression és Advanced Security.

  Read the article

• How do I allow all possible IPs for Gmail servers through my ufw firewall?

  - by nomadicME

  I am currently using the following rule: ufw allow out from my_local_ip to any port 587 This is a little too lax for my liking. I would like to tighten it up and restrict it to only gmail's smtp server ip addresses, but they are always changing. I used to just wait until an outgoing email didn't make it to its destination, then check syslog for the ip address that was blocked, then add that to the ufw configure script. However, now I have a need for much more reliability. Is there any way to use smtp.gmail.com in ufw? I don't think so, but thought I would ask. Any other ideas? Thanks.

  Read the article

• books about Firewall development

  - by VP

  Hi, i was just asked today, but i couldn't answer precisely so that's why i'm asking here :-) There is any book about Firewall design and implementations (Unix environment and C)? For sure, i could recommend TCP/IP books, and what i did, but there is some design decisions, that are not related with TCP/IP. For sure, i said about the netfilter/iptables (RTFSC) but as well we cannot assume that the netfilter/iptables is the best approach since we don't have too many baselines (ok, we could compare it with PF, but again, read source code to understand design decisions is not always the best way). So if anybody knows a book about this theme, please shoot it!

  Read the article

• enable iptables firewall on linux

  - by user13278061

   Here is a very basic set of instruction to setup a simple iptables firewall configuration on linux (redhat) Enable firewall log as root thenenter the following command, it launch a text gui #> setup first screen: Choose firewall configuration second screen: choose "Enabled" then "Customize" third screen: select you interface in "Trusted Devices", select "Allow Incoming" for "SSH" "Telnet" "FTP" (add eventually other ports, then press "OK" (2 times, then "Quit") At that point the firewall is enabled. You can start/stop/monitor using service iptables start/stop/status Change timeout to changed the tcp established connection timeout #> echo 120 >    /proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_timeout_established Monitor connection in iptables tables for example if you want to track a connection establish from a host  152.68.65.207 #> cat /proc/net/ip_conntrack |grep 152.68.65.207

  Read the article

• Connecting to device behind firewall

  - by tim

  I have a wpf app that needs to communicate(exchange data) with a custom designed device (we can modify the code for the device). Do I have any options to connect to the device if it is behind a firewall via http? I was hoping there would be a method where the admin would not have to forward any specific ports or do anything on his end. I assume the issue is how would I address the device from my app. I know SOAP over SMTP is one option. Is another option where the device could chatter out to my application via http?

  Read the article

• Cablemodem (SBG6580) firewall denying some outbound traffic? Why? Not configured [migrated]

  - by lairdb

  I finally got around to turning the syslog on for my cablemodem (Motorola Surfboard SBG6580) and I'm seeing about the expected amount of inbound attackage being blocked... 2014-05-30 21:59:02 Local0.Alert 192.168.111.1 May 31 04:58:56 2014 SYSLOG[0]: [Host 192.168.111.1] UDP 12.230.209.198,4500 --> 66.27.xx.xx,61459 DENY:Firewall interface [IP Fragmented Packet] attack 2014-05-30 21:59:02 Local0.Alert 192.168.111.1 May 31 04:58:56 2014 SYSLOG[0]: [Host 192.168.111.1] TCP 17.172.232.109,5223 --> 66.27.xx.xx,53814 DENY:Firewall interface access request 2014-05-30 21:59:02 Local0.Alert 192.168.111.1 May 31 04:58:57 2014 SYSLOG[0]: [Host 192.168.111.1] UDP 12.230.209.198,443 --> 66.27.xx.xx,53385 DENY: Firewall interface [IP Fragmented Packet] attack 2014-05-30 21:59:02 Local0.Alert 192.168.111.1 May 31 04:58:57 2014 SYSLOG[0]: [Host 192.168.111.1] UDP 12.230.209.198,4500 --> 66.27.xx.xx,61459 DENY:Firewall interface [IP Fragmented Packet] attack 2014-05-30 21:59:10 Local0.Alert 192.168.111.1 May 31 04:59:04 2014 SYSLOG[0]: [Host 192.168.111.1] UDP 12.230.209.198,443 --> 66.27.xx.xx,59960 DENY: Firewall interface [IP Fragmented Packet] attack 2014-05-30 21:59:10 Local0.Alert 192.168.111.1 May 31 04:59:04 2014 SYSLOG[0]: [Host 192.168.111.1] UDP 12.230.209.198,4500 --> 66.27.xx.xx,61459 DENY:Firewall interface [IP Fragmented Packet] attack ...and that's great. (Sad, but great.) But I'm also seeing a HUGE amount of what appears to be denied outbound connectivity: 2014-05-30 16:30:10 Local0.Alert 192.168.111.1 May 30 23:30:04 2014 SYSLOG[0]: [Host 192.168.111.1] TCP 192.168.111.100,58969 --> 38.81.66.127,443 DENY: Inbound or outbound access request 2014-05-30 16:30:10 Local0.Alert 192.168.111.1 May 30 23:30:04 2014 SYSLOG[0]: [Host 192.168.111.1] TCP 192.168.111.100,58969 --> 38.81.66.127,443 DENY: Inbound or outbound access request 2014-05-30 16:30:10 Local0.Alert 192.168.111.1 May 30 23:30:04 2014 SYSLOG[0]: [Host 192.168.111.1] TCP 192.168.111.100,58965 --> 162.222.41.13,443 DENY: Inbound or outbound access request 2014-05-30 16:30:10 Local0.Alert 192.168.111.1 May 30 23:30:04 2014 SYSLOG[0]: [Host 192.168.111.1] TCP 192.168.111.100,58965 --> 162.222.41.13,443 DENY: Inbound or outbound access request 2014-05-30 16:30:10 Local0.Alert 192.168.111.1 May 30 23:30:04 2014 SYSLOG[0]: [Host 192.168.111.1] TCP 192.168.111.100,58964 --> 38.81.66.179,443 DENY: Inbound or outbound access request 2014-05-30 16:30:10 Local0.Alert 192.168.111.1 May 30 23:30:04 2014 SYSLOG[0]: [Host 192.168.111.1] TCP 192.168.111.100,58964 --> 38.81.66.179,443 DENY: Inbound or outbound access request ...and Spot checking suggests that it's all legitimate traffic (Opening connections to CrashPlan, etc.), I have no restrictions configured in the modem; I don't see why it should be blocking anything. Am I misreading the log entry, and it's not actually being denied? (Seems unlikely.) Is the ISP (TWC) pushing deny tables that are not exposed in the UI? (Tinfoil hat too tight.) I'm confused. (The good news, such as it is, is that AFAIK I'm not experiencing any actual issues... but maybe I am; tough to tell.) Thanks.

  Read the article

• How to add an iptables rule with source IP address

  - by ???

  I have a bash script that starts with this: if [[ $EUID -ne 0 ]]; then echo "Permission denied (are you root?)." exit 1 elif [ $# -ne 1 ] then echo "Usage: install-nfs-server <client network/CIDR>" echo "$ bash install-nfs-server 192.168.1.1/24" exit 2 fi; I then try to add the iptables rules for NFS as follows: iptables -A INPUT -i eth0 -p tcp -s $1 --dport 111 -m state --state NEW,ESTABLISHED -j ACCEPT iptables -A OUTPUT -o eth0 -p tcp --sport 111 -m state --state ESTABLISHED -j ACCEPT iptables -A INPUT -i eth0 -p udp -s $1 --dport 111 -m state --state NEW,ESTABLISHED -j ACCEPT iptables -A OUTPUT -o eth0 -p udp --sport 111 -m state --state ESTABLISHED -j ACCEPT service iptables save service iptables restart I get the error: Try iptables -h' or 'iptables --help' for more information. Bad argument111' Try iptables -h' or 'iptables --help' for more information. Bad argument111' Saving firewall rules to /etc/sysconfig/iptables: ^[[60G[^[[0;32m OK ^[[0;39m]^M Flushing firewall rules: ^[[60G[^[[0;32m OK ^[[0;39m]^M Setting chains to policy ACCEPT: filter ^[[60G[^[[0;32m OK ^[[0;39m]^M Unloading iptables modules: ^[[60G[^[[0;32m OK ^[[0;39m]^M Applying iptables firewall rules: ^[[60G[^[[0;32m OK ^[[0;39m]^M Loading additional iptables modules: ip_conntrack_netbios_ns ^[[60G[^[[0;32m OK ^[[0;39m]^M When I open /etc/sysconfig/iptables these are the rules: # Generated by iptables-save v1.3.5 on Mon Mar 26 08:00:42 2012 *filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [466:54208] :RH-Firewall-1-INPUT - [0:0] -A INPUT -j RH-Firewall-1-INPUT -A FORWARD -j RH-Firewall-1-INPUT -A OUTPUT -o eth0 -p tcp -m tcp --sport 111 -m state --state ESTABLISHED -j ACCEPT -A OUTPUT -o eth0 -p udp -m udp --sport 111 -m state --state ESTABLISHED -j ACCEPT -A OUTPUT -o eth0 -p tcp -m tcp --sport 111 -m state --state ESTABLISHED -j ACCEPT -A OUTPUT -o eth0 -p udp -m udp --sport 111 -m state --state ESTABLISHED -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 111 -j ACCEPT -A RH-Firewall-1-INPUT -p udp -m state --state NEW -m udp --dport 111 -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 111 -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 111 -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 111 -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 111 -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 111 -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 111 -j ACCEPT -A RH-Firewall-1-INPUT -i lo -j ACCEPT -A RH-Firewall-1-INPUT -p icmp -m icmp --icmp-type any -j ACCEPT -A RH-Firewall-1-INPUT -p esp -j ACCEPT -A RH-Firewall-1-INPUT -p ah -j ACCEPT -A RH-Firewall-1-INPUT -d 224.0.0.251 -p udp -m udp --dport 5353 -j ACCEPT -A RH-Firewall-1-INPUT -p udp -m udp --dport 631 -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m tcp --dport 631 -j ACCEPT -A RH-Firewall-1-INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited COMMIT # Completed on Mon Mar 26 08:00:42 2012 ~ "/etc/sysconfig/iptables" 32L, 1872C I've also tried: iptables -I RH-Firewall-1-INPUT 1 -m state --state NEW -m tcp -p tcp --source $1 --dport 111 -j ACCEPT iptables -I RH-Firewall-1-INPUT 2 -m udp -p udp --source $1 --dport 111 -j ACCEPT

  Read the article

• WCF push to client through firewall?

  - by Sire

  See also How does a WCF server inform a WCF client about changes? (Better solution then simple polling, e.g. Coment or long polling) I need to use push-technology with WCF through client firewalls. This must be a common problem, and I know for a fact it works in theory (see links below), but I have failed to get it working, and I haven't been able to find a code sample that demonstrates it. Requirements: WCF Clients connects to server through tcp port 80 (netTcpBinding). Server pushes back information at irregular intervals (1 min to several hours). Users should not have to configure their firewalls, server pushes must pass through firewalls that have all inbound ports closed. TCP duplex on the same connection is needed for this, a dual binding does not work since a port has to be opened on the client firewall. Clients sends heartbeats to server at regular intervals (perhaps every 15 mins) so server knows client is still alive. Server is IIS7 with WAS. The solution seems to be duplex netTcpBinding. Based on this information: WCF through firewalls and NATs Keeping connections open in IIS But I have yet to find a code sample that works.. I've tried combining the "Duplex" and "TcpActivation" samples from Microsoft's WCF Samples without any luck. Please can someone point me to example code that works, or build a small sample app. Thanks a lot!

  Read the article

• Webservice randomly dropping connections - possibly due to firewall nonevent data?

  - by adam

  I have a hosted webapp which requests data from a REST webservice in our office. Each page calls one (or several) webservices, which go from our host, via our firewall (a Watchguard Firebox) to a server in our office. All of a sudden, the app has dramatically slowed. We have determined that the webservice is timing out at random when called externally (it's fine when called within the office network). I'm pretty certain it's our connection which is dropping the webservice call, so I've written a quick php/curl script which calls the webservice over many iterations and shows the various timings. Below is an example output, showing both a failed and a successful call (with a 5 second timeout): http_code namelookup_time connect_time pretransfer_time starttransfer_time total_time 1 0 0.000096 0.0342 0.0000 0.0000 0.0342 2 200 0.000052 0.0332 0.1327 0.1751 0.1752 As per iteration #1 above, failed requests seem to be failing between connect and pretransfer. I'm not sure if this shows that the connection is successfully past the firewall, or could the firewall still cause an issue? Our firewall is showing a series of nondata event log messages for the relevant access rule. Our IT team tells me these are routine, although I can find no mention of these in Google. I'm not sure if this fits in between connect and pretransfer. Having elinated the webservice server (by testing internally) and the live webapp (by testing different code on different external servers, I am left suspecting the connection to the office. Could the firebox nondata events be causing a problem between connect and pretransfer?

  Read the article

• Does ICS modify windows firewall policies in the registry?

  - by insipid

  I had a host machine I wanted to enable ICS on. First I realized that doing so was not possible until I enabled the Windows Firewall. Once I enabled the firewall and set up ICS, I noticed due to group policy I could no longer disable the firewall. Also, any ports I tried to open seemed to be ignored. Although nothing seemed to be configured when I used the mmc snap-in to view local computer policy, when I checked the registry I noticed several policies set there in HKLM (such as disabling AllowLocalPolicyMerge). I was able to remove the policies from the registry and my open ports worked, but they were eventually re-added without my input. The network I am sharing the internet from is an "unsecured" wireless network with an authentication page, is it possible that this is causing those policies to be set? Did ICS set those policies? When you go to the properties of the ICS enabled adapter and go to the ICS settings it takes you to a tab called services where you can add and remove "services running on your network that internet users can access". Is this related to the windows firewall?

  Read the article

• Why my Buffalo router keeps on sending rdp, netbios, ftp, http requests?

  - by user192702

  I have the following network setup: Buffalo Router (192.168.100.1) < Watchguard XTM21 (192.168.100.13) < PC For some reason I keep on seeing the following repeating on my XTM21's Traffic Monitor. While I have enabled Port Forwarding, none of the ports reported below were enabled. Can someone let me know why I'm seeing all of these? 2013-10-19 23:37:56 Deny 192.168.100.1 192.168.100.13 ftp/tcp 4013 21 0-External Firebox Denied 60 64 (Unhandled External Packet-00) proc_id="firewall" rc="101" tcp_info="offset 10 S 282700472 win 5840" Traffic 2013-10-19 23:37:59 Deny 192.168.100.1 192.168.100.13 http/tcp 2459 80 0-External Firebox Denied 60 64 (Unhandled External Packet-00) proc_id="firewall" rc="101" tcp_info="offset 10 S 296571237 win 5840" Traffic 2013-10-19 23:38:02 Deny 192.168.100.1 192.168.100.13 8000/tcp 3244 8000 0-External Firebox blocked ports 60 64 (Internal Policy) proc_id="firewall" rc="101" tcp_info="offset 10 S 298709937 win 5840" Traffic 2013-10-19 23:38:05 Deny 192.168.100.1 192.168.100.13 8000/tcp 3244 8000 0-External Firebox blocked ports 60 64 (Internal Policy) proc_id="firewall" rc="101" tcp_info="offset 10 S 298709937 win 5840" Traffic 2013-10-19 23:38:05 Deny 192.168.100.1 192.168.100.13 rdp/tcp 3896 3389 0-External Firebox Denied 60 64 (Unhandled External Packet-00) proc_id="firewall" rc="101" tcp_info="offset 10 S 290482691 win 5840" Traffic 2013-10-19 23:38:08 Deny 192.168.100.1 192.168.100.13 netbios-ns/udp 2110 137 0-External Firebox Denied 78 64 (Unhandled External Packet-00) proc_id="firewall" rc="101" Traffic 2013-10-19 23:38:32 Deny 192.168.100.1 192.168.100.13 ftp/tcp 4025 21 0-External Firebox Denied 60 64 (Unhandled External Packet-00) proc_id="firewall" rc="101" tcp_info="offset 10 S 321868558 win 5840" Traffic 2013-10-19 23:38:35 Deny 192.168.100.1 192.168.100.13 http/tcp 2471 80 0-External Firebox Denied 60 64 (Unhandled External Packet-00) proc_id="firewall" rc="101" tcp_info="offset 10 S 325918731 win 5840" Traffic 2013-10-19 23:38:38 Deny 192.168.100.1 192.168.100.13 8000/tcp 3256 8000 0-External Firebox blocked ports 60 64 (Internal Policy) proc_id="firewall" rc="101" tcp_info="offset 10 S 327854525 win 5840" Traffic 2013-10-19 23:38:41 Deny 192.168.100.1 192.168.100.13 8000/tcp 3256 8000 0-External Firebox blocked ports 60 64 (Internal Policy) proc_id="firewall" rc="101" tcp_info="offset 10 S 327854525 win 5840" Traffic 2013-10-19 23:38:41 Deny 192.168.100.1 192.168.100.13 rdp/tcp 3896 3389 0-External Firebox Denied 60 64 (Unhandled External Packet-00) proc_id="firewall" rc="101" tcp_info="offset 10 S 327101423 win 5840" Traffic 2013-10-19 23:38:44 Deny 192.168.100.1 192.168.100.13 netbios-ns/udp 2110 137 0-External Firebox Denied 78 64 (Unhandled External Packet-00) proc_id="firewall" rc="101" Traffic

  Read the article

• Virtual environment firewall with CSF + iptables rules on VM?

  - by luison

  We are getting into virtualization with a Proxmox VE (OpenVZ + KVM) server. Our plan for firewall is to have CSF (http://configserver.com/cp/csf.html) running on the host machine as we've had a reasonable good experience with it in the past. Apart from that we plan simple firewall rules on the VM machines (mostly OpenVZ containers with same kernel) and maybe fail2ban simple specific rules. I would appreciate comments with anyone with similar experiences? I understand all traffic comes via the host machine so a combined firewall there with specific firewalling on the VM should work, alltough some iptables rules are hard to get to work on OpenVZ containers.

  Read the article

• Firewall Deep Inspection Updates and Antivirus Subscription, worth it?

  - by msemack

  I realize that this is a subjective question, but I'm trying to get some experiences We have Juniper firewalls in our organization (SSG-320M, SSG-5, and some old NS-5GT). We have the option of a yearly subscription for: Deep Inspection Signature Updates Juniper-Kaspersky Antivirus I seem similar services available from other Firewall vendors. We have Symantec Endpoint Protection deployed to all workstations and servers, plus a dedicated appliance for e-mail spam/virus filtering. So, I'm not sure what these firewall-base services will bring to the table that I don't already have. I would appreciate some feedback from people using these firewall services (Juniper or otherwise). Are these services generally worth it? Do they really catch anything? Do they interfere with normal traffic (false positives)?

  Read the article

• VPN is working, except for DNS lookups. Firewall (Cisco ASA 5505) issue?

  - by macke

  I've got the following set up: LAN -> DHCP / DNS / VPN server (OSX 10.6) -> Cisco ASA 5505 -> WAN Connecting to the LAN via VPN works fine. I get all the details properly and I can ping any host on the internal network using their IP. However, I can't do any host lookups whatsoever. I've looked through the logs on and found this nugget in the firewall log: 3 Sep 08 2010 10:46:40 305006 10.0.0.197 65371 portmap translation creation failed for udp src inside:myhostname.local/53 dst inside:10.0.0.197/65371 Port 53 is dns services, no? Because of that log entry, I'm thinking that the issue is with the firewall, not the server. Any ideas? Please keep in mind that I have very little knowledge and experience with this kind of firewall and the little experience I do have is with the ASDM GUI console, not the CLI console.

  Read the article

• How do I examine my Windows firewall outbound rules?

  - by David

  I need a program to listen to port 9000 on localhost with my Windows firewall. I've created an outgoing and an incoming rule for my program but I can only see my incomming rule in the Windows firewall general menu? I've also noticed that I've many more outgoing rules in my outgoing rule menu but I can only see 4 outgoing rules in my general firewall menu but I see many many more incomming rules? The program doesn't listen to port 9000 or it doesn't working. I've also tried netstat -a -p to no avail. I didn't see 0.0.0.0:9000 in the output? How can I check if my program listen to port 9000 or connect to port 9000 when it's open?

  Read the article

• Running a webserver behind a firewall, is it secure?

  - by i.am.intern

  Currently we have a Linux-based firewall which NAT-ing our public IP address to give internet access to our staff's PCs and a Windows Server 2003 for internal filesharing. I want to host Redmine/SVN (a bugtracker) internally behind this firewall using a Linux server. This webserver will be accessed by our clients externally so they can post bug reports. This means that I have to open port 80 & 22 at the firewall to give access to the webserver and me to SSH it from home. However, let's say I'm using password-based SSH for the webserver and somebody cracked it. Does that mean the cracker could ping and access other servers and PCs in the network?

  Read the article

• What firewall ports do I need to open when using FTPS?

  - by anoopm

  I need to access an ftps server (vsftpd) on a vendor's site. The vendor has a firewall in front of the ftps server and I have a firewall in front of my ftps client. I understand that ports 990, 991 and maybe 989 need to be opened up for control traffic. When looking at it from the vendor's firewall perspective, should these ports be opened up for both inbound and outbound traffic? What about ports for the DATA channel? Do I have to open all ports above 1000? And should I do it for both inbound and outbound traffic? TIA for your help.

  Read the article

• How can I measure TCP timeout limit on NAT firewall for setting keepalive interval?

  - by jmanning2k

  A new (NAT) firewall appliance was recently installed at $WORK. Since then, I'm getting many network timeouts and interruptions, especially for operations which would require the server to think for a bit without a response (svn update, rsync, etc.). Inbound SSH sessions over VPN also timeout frequently. That clearly suggests I need to adjust the TCP (and ssh) keepalive time on the servers in question in order to reduce these errors. But what is the appropriate value I should use? Assuming I have machines on both sides of the firewall between which I can make a connection, is there a way to measure what the time limit on TCP connections might be for this firewall? In theory, I would send a packet with gradually increasing intervals until the connection is lost. Any tools that might help (free or open source would be best, but I'm open to other suggestions)? The appliance is not under my control, so I can't just get the value, though I am attempting to ask what it currently is and if I can get it increased.

  Read the article

• How to open a server port outside of an OpenVPN tunnel with a pf firewall on OSX (BSD)

  - by Timbo

  I have a Mac mini that I use as a media server running XBMC and serves media from my NAS to my stereo and TV (which has been color calibrated with a Spyder3Express, happy). The Mac runs OSX 10.8.2 and the internet connection is tunneled for general privacy over OpenVPN through Tunnelblick. I believe my anonymous VPN provider pushes "redirect_gateway" to OpenVPN/Tunnelblick because when on it effectively tunnels all non-LAN traffic in- and outbound. As an unwanted side effect that also opens the boxes server ports unprotected to the outside world and bypasses my firewall-router (Netgear SRX5308). I have run nmap from outside the LAN on the VPN IP and the server ports on the mini are clearly visible and connectable. The mini has the following ports open: ssh/22, ARD/5900 and 8080+9090 for the XBMC iOS client Constellation. I also have Synology NAS which apart from LAN file serving over AFP and WebDAV only serves up an OpenVPN/1194 and a PPTP/1732 server. When outside of the LAN I connect to this from my laptop over OpenVPN and over PPTP from my iPhone. I only want to connect through AFP/548 from the mini to the NAS. The border firewall (SRX5308) just works excellently, stable and with a very high throughput when streaming from various VOD services. My connection is a 100/10 with a close to theoretical max throughput. The ruleset is as follows Inbound: PPTP/1723 Allow always to 10.0.0.40 (NAS/VPN server) from a restricted IP range >corresponding to possible cell provider range OpenVPN/1194 Allow always to 10.0.0.40 (NAS/VPN server) from any Outbound: Default outbound policy: Allow Always OpenVPN/1194 TCP Allow always from 10.0.0.40 (NAS) to a.b.8.1-a.b.8.254 (VPN provider) OpenVPN/1194 UDP Allow always to 10.0.0.40 (NAS) to a.b.8.1-a.b.8.254 (VPN provider) Block always from NAS to any On the Mini I have disabled the OSX Application Level Firewall because it throws popups which don't remember my choices from one time to another and that's annoying on a media server. Instead I run Little Snitch which controls outgoing connections nicely on an application level. I have configured the excellent OSX builtin firewall pf (from BSD) as follows pf.conf (Apple App firewall tie-ins removed) (# replaced with % to avoid formatting errors) ### macro name for external interface. eth_if = "en0" vpn_if = "tap0" ### wifi_if = "en1" ### %usb_if = "en3" ext_if = $eth_if LAN="{10.0.0.0/24}" ### General housekeeping rules ### ### Drop all blocked packets silently set block-policy drop ### all incoming traffic on external interface is normalized and fragmented ### packets are reassembled. scrub in on $ext_if all fragment reassemble scrub in on $vpn_if all fragment reassemble scrub out all ### exercise antispoofing on the external interface, but add the local ### loopback interface as an exception, to prevent services utilizing the ### local loop from being blocked accidentally. ### set skip on lo0 antispoof for $ext_if inet antispoof for $vpn_if inet ### spoofing protection for all interfaces block in quick from urpf-failed ############################# block all ### Access to the mini server over ssh/22 and remote desktop/5900 from LAN/en0 only pass in on $eth_if proto tcp from $LAN to any port {22, 5900, 8080, 9090} ### Allow all udp and icmp also, necessary for Constellation. Could be tightened. pass on $eth_if proto {udp, icmp} from $LAN to any ### Allow AFP to 10.0.0.40 (NAS) pass out on $eth_if proto tcp from any to 10.0.0.40 port 548 ### Allow OpenVPN tunnel setup over unprotected link (en0) only to VPN provider IPs ### and port ranges pass on $eth_if proto tcp from any to a.b.8.0/24 port 1194:1201 ### OpenVPN Tunnel rules. All traffic allowed out, only in to ports 4100-4110 ### Outgoing pings ok pass in on $vpn_if proto {tcp, udp} from any to any port 4100:4110 pass out on $vpn_if proto {tcp, udp, icmp} from any to any So what are my goals and what does the above setup achieve? (until you tell me otherwise :) 1) Full LAN access to the above ports on the mini/media server (including through my own VPN server) 2) All internet traffic from the mini/media server is anonymized and tunneled over VPN 3) If OpenVPN/Tunnelblick on the mini drops the connection, nothing is leaked both because of pf and the router outgoing ruleset. It can't even do a DNS lookup through the router. So what do I have to hide with all this? Nothing much really, I just got carried away trying to stop port scans through the VPN tunnel :) In any case this setup works perfectly and it is very stable. The Problem at last! I want to run a minecraft server and I installed that on a separate user account on the mini server (user=mc) to keep things partitioned. I don't want this server accessible through the anonymized VPN tunnel because there are lots more port scans and hacking attempts through that than over my regular IP and I don't trust java in general. So I added the following pf rule on the mini: ### Allow Minecraft public through user mc pass in on $eth_if proto {tcp,udp} from any to any port 24983 user mc pass out on $eth_if proto {tcp, udp} from any to any user mc And these additions on the border firewall: Inbound: Allow always TCP/UDP from any to 10.0.0.40 (NAS) Outbound: Allow always TCP port 80 from 10.0.0.40 to any (needed for online account checkups) This works fine but only when the OpenVPN/Tunnelblick tunnel is down. When up no connection is possbile to the minecraft server from outside of LAN. inside LAN is always OK. Everything else functions as intended. I believe the redirect_gateway push is close to the root of the problem, but I want to keep that specific VPN provider because of the fantastic throughput, price and service. The Solution? How can I open up the minecraft server port outside of the tunnel so it's only available over en0 not the VPN tunnel? Should I a static route? But I don't know which IPs will be connecting...stumbles How secure would to estimate this setup to be and do you have other improvements to share? I've searched extensively in the last few days to no avail...If you've read this far I bet you know the answer :)

  Read the article

• Why is file sharing over internet still working, despite all firewall exceptions for filesharing being disabled?

  - by Triynko

  Every exception in my windows server firewall that starts with "File and Printer Sharing" is disabled (ordered by name, so that includes domain, public (active), and private profiles). The Network and Sharing Center's options for everything except password protected sharing are off. Why would I still be able to access a network share on that server via an address like "\\my.server.com\" over the internet? The firewall is on for all profiles and blocking incoming connections by default. A "netstat -an" command on the server reveals the share connection is occurring over port 445 (SMB). I restarted the client to ensure it was actually re-establishing a new connection successfully. Is the "Password protected sharing: On" option in Network and Sharing Center bypassing the firewall restrictions, or adding some other exception somewhere that I'm missing? EDIT: "Custom" rules are not the problem. It's the "built-in" rules for Terminal Services that was the problem. Can you believe port 445 (File Sharing Port) has to be wide open to the internet to use Terminal Services Licensing?)

  Read the article

• Is it generally a bad idea to have other types of virtual appliances installed along side a firewall

  - by MGSoto

  I want to run my Firewall/NAT software (pfsense) and an internal NAS (looking at freenas right now) for my SOHO on one machine. Right now I have them separated on two different machines, but I'd like to consolidate them. Is this generally a bad idea? I see the security concern where if the firewall or host OS is compromised, then your data is essentially screwed. But is it really a concern for me?

  Read the article

• How can I scan from Canon PIXMA MX700 without disabling OS X firewall?

  - by Justin Love

  I have a Canon PIXMA MX700 connected by ethernet. When I first bought it I was using OS X 10.4, and scanner-initiated scanning worked fine. After upgrading to 10.6, neither scanner-initiated or scanning from MP Navigator EX works with the firewall enabled. The firewall lists exceptions for three applications: Canon IJ Network Scan Utility.app Canon IJ Network Scanner Selector.app MP Navigator EX 1.0.app I get no further blocked warnings, and /var/log/appfirewall.log lists nothing for today (my latest attempt to use it).

  Read the article

• If I reset the Windows Firewall with netsh will programs re-prompt for access?

  - by Bob

  If I run the following command: netsh advfirewall reset The windows firewall will get flushed back to it's defaults and looses any program specific rules. Will programs that require firewall access start prompting the user after the reset is triggered?

  Read the article

< Previous Page | 7 8 9 10 11 12 13 14 15 16 17 18  | Next Page >