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Networking

RHEL / CentOS Linux 7 Enable Ping Access In Docker Container

I’m using RHEL 7.1-4 container on a RHEL /CentOS Linux 7.x server. However, I’m unable to ping external site/IP address using the ping command. I’m getting the following error on screen:

ping: Operation not permitted

How do I fix this problem?
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How To Mount a Remote Directory With SSHFS on a Linux

How can I mount a remote directory with ssh on a Linux bases system? How do I use SSHFS to mount remote file systems over SSH on a Ubuntu or Debian/RHEL/CentOS/Arch Linux system?
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FreeBSD Unix Find Out Which Programs Are Listing On a Given Port Number

I‘m a new FreeBSD Unix system user. How can I find out the process/programs names listing on a certain port on a FreeBSD Unix systems using command line? How do I lookup the process which is currently bound to the given network port on a FreeBSD server?
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Howto Configure PFSense Site-to-Site IPSec VPN Tunnel For Remote Access

I work from a small office/home office and I need to set up an IPSec site-to-site VPN between a Cisco/OpeNBSD IPSec-enabled gateway and firewall running PFSense. How do I configure the VPN tunnel so that I can access remote subnet and servers behiend a Cisco firewall/router securely? How do I setup a tunnel mode configuration which will provide you with an encrypted site-to-site network, allowing networks at multiple remote locations to be able to securely communicate using my PFSense located in my SOHO?
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FreeBSD Force DHCP Client (dhclient) to Renew IP Address To Get A New Lease

I have a Linux DD-WRT router DHCP server running on my network. How can I force my FreeBSD based dhcp client to get a new lease from this Linux based router? What is the command in FreeBSD equivalent to Windows’ “ipconfig /renew” command?
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CentOS / RHEL 7 Restart / Stop / Start Networking Command

I recently installed CentOS Linux version 7 or Red Hat Enterprise Linux version 7. How can I restart networking service using command line options? How can I start / stop and restart networking service on a CentOS/RHEL 7 based system?
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Fedora Linux 20: Install Broadcom-wl STA BCM43228 Wireless Driver

I‘m using Dell / Lenovo laptop with Broadcom’s IEEE 802.11a/b/g/n based wireless card. How can I install Broadcom-wl STA BCM4322 Wireless driver on a Fedora Linux version 20?
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curl Command Resume Broken Download

I know wget can resume a failed download. I am on a Mac OS X and do now want to install wget command. How can I resume a failed download using curl command on Linux or Unix-like systems?
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Linux: Log Suspicious Martian Packets / Un-routable Source Addresses

I run a web-server and I would like to log packets with un-routable source addresses on Linux operating system. How can I log spoofed packets on Debian / Ubuntu / CentOS / RHEL / Linux based server? How can I log a Martian packet (packet from Mars) on Linux operating systems?
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Increase NFS Client Mount Point Security For a Web-Server noexec, nosuid, nodev Options

I am using NFS server version 4.x on a CentOS/RHEL based system. I’m mounting my shared /var/www/ directory on five Apache based nodes using the following syntax:

mount -t nfs4 -o rw,intr,hard,proto=tcp rocknas02:/httproot/www /var/www/

I noticed that due to bug in my app user can sometime upload executable or other device files to get out of chrooted Apache server. How can I prevent such security issues on a CentOS or RHEL based NFS client and sever setup?
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