Difference between revisions of "Installation"

From FOG Project
Jump to: navigation, search
m
(LXC)
 
(27 intermediate revisions by 2 users not shown)
Line 2: Line 2:
 
Before diving right into the installation of FOG you need to decide which server OS you are going to use. FOG is made to install on RedHat based distro CentOS, Fedora, RHEL amongst others as well as Debian, Ubuntu and Arch Linux. Choose whichever you like most and have knowledge about! FOG is known to work with any of the above noted systems. Many [[Installation#Installation_manuals|installation manuals]] are available.
 
Before diving right into the installation of FOG you need to decide which server OS you are going to use. FOG is made to install on RedHat based distro CentOS, Fedora, RHEL amongst others as well as Debian, Ubuntu and Arch Linux. Choose whichever you like most and have knowledge about! FOG is known to work with any of the above noted systems. Many [[Installation#Installation_manuals|installation manuals]] are available.
  
This listing is for informational purposes only, as the required components will be automatically downloaded and installed by the FOG installation script: PHP 5/6/7, MySql 5+, Apache 2+, DHCP (any!), TFTP, FTP, NFS
+
This listing is for informational purposes only, as the required components will be automatically downloaded and installed by the FOG installation script: PHP 5/7, MySql 5+/MariaDB 10+, Apache 2+, DHCP (pretty much any!), TFTP, FTP, NFS
  
 
The LAMP setup can also be easily adjusted for a "WAMP (Windows Apache MySQL PHP) system" though will require a bit more knowledge of what packages to use and how to integrate with the FOG system.
 
The LAMP setup can also be easily adjusted for a "WAMP (Windows Apache MySQL PHP) system" though will require a bit more knowledge of what packages to use and how to integrate with the FOG system.
 +
 +
Please choose the distribution you have the most knowledge about, but the below list has the best support in FOG 1.3.0 right now. This list is by no means an absolute list to follow, though.
 +
 +
* Ubuntu 16 or higher
 +
 +
* Debian 8 or higher
 +
 +
* CentOS 7 or higher
 +
 +
* Red Hat 6 or higher
 +
 +
* Fedora 22 or higher
 +
 +
* Any version of Arch.
  
 
== Download FOG ==
 
== Download FOG ==
 +
Please see: [[Getting_FOG]]
  
=== Official archive ===
+
== Installer ==
FOG was first hosted on the well known open source project platform SourceForge and you still find the current code plus released versions [[https://sourceforge.net/projects/freeghost/ there]] (download as well linked on the [[https://fogproject.org/ official homepage]]. You'll get a comressed tar archive (.tar.gz) which you need to extract (anywhere is ok) before you can run the installer script ('''root privileges needed!''').
+
The FOG installer comes as a complex shell script that will handle all the package installs and configuring the services for you. It must be run as root (sudo works as well) to be able to set things up properly. Running the installer on a new system for the first time it will ask you a couple of questions regarding your network configuration and services you want to install.
  
sudo -i
+
=== Modes ===
wget http://downloads.sourceforge.net/project/freeghost/FOG/fog_1.2.0/fog_1.2.0.tar.gz
+
FOG can be installed in two different modes. First is the normal FOG server which does all of the work. Choose this option if you only want have a single FOG server in your network. The second option is to install a FOG storage node which will serve as a second place to store images on and serve images to more clients (when doing unicast). [[InstallationModes|Here]] you can find some more information about the two modes.
tar xzf fog_1.2.0.tar.gz
 
cd fog_1.2.0/bin
 
./installfog.sh
 
  
To get the very latest version of FOG you need to follow one of the following methods. Each has its pros so you will need to figure out which you want to use:
+
  FOG Server installation modes:
{{:Upgrade_to_trunk}}
+
      * Normal Server: (Choice N)
 +
          This is the typical installation type and
 +
          will install all FOG components for you on this
 +
          machine. Pick this option if you are unsure what to pick.
 +
 +
      * Storage Node: (Choice S)
 +
          This install mode will only install the software required
 +
          to make this server act as a node in a storage group
  
== Installer options ==
+
=== Command line options ===
Full Server
+
The FOG installer has quite a few command line options. See the output below. You might want force FOG to setup the web interface via HTTPS, change the default PXE boot file or web root directory.
Storage Node
 
/opt/fog/.fogsettings
 
Backups!!
 
  
 +
./installfog.sh --help
 +
Usage: ./installfog.sh [-h?dEUuHSCKYXTFA] [-f <filename>] [-N <databasename>]
 +
[-D </directory/to/document/root/>] [-c <ssl-path>]
 +
[-W <webroot/to/fog/after/docroot/>] [-B </backup/path/>]
 +
[-s <192.168.1.10>] [-e <192.168.1.254>] [-b <undionly.kpxe>]
 +
-h -? --help Display this info
 +
-o    --oldcopy Copy back old data
 +
-d    --no-defaults Don't guess defaults
 +
-U    --no-upgrade Don't attempt to upgrade
 +
-H    --no-htmldoc No htmldoc, means no PDFs
 +
-S    --force-https Force HTTPS for all comunication
 +
-C    --recreate-CA Recreate the CA Keys
 +
-K    --recreate-keys Recreate the SSL Keys
 +
-Y -y --autoaccept Auto accept defaults and install
 +
-f    --file Use different update file
 +
-c    --ssl-path Specify the ssl path
 +
              defaults to /opt/fog/snapins/ssl
 +
-D    --docroot Specify the Apache Docroot for fog
 +
              defaults to OS DocumentRoot
 +
-W    --webroot Specify the web root url want fog to use
 +
            (E.G. http://127.0.0.1/fog,
 +
                  http://127.0.0.1/)
 +
            Defaults to /fog/
 +
-B    --backuppath Specify the backup path
 +
      --uninstall Uninstall FOG
 +
-s    --startrange DHCP Start range
 +
-e    --endrange DHCP End range
 +
-b    --bootfile DHCP Boot file
 +
-E    --no-exportbuild Skip building nfs file
 +
-X    --exitFail Do not exit if item fails
 +
-T    --no-tftpbuild Do not rebuild the tftpd config file
 +
-F    --no-vhost Do not overwrite vhost file
 +
-A    --arm-support Install kernel and initrd for ARM platforms
 +
 +
=== .fogsettings ===
 +
 +
Full article on the .fogsettings file can be found here: [[.fogsettings]]
 +
 +
=== Backups ===
 +
TBD
 +
 +
=== Errorlog ===
 +
TBD
  
 
== Installation manuals ==
 
== Installation manuals ==
Line 35: Line 94:
  
 
=== Debian ===
 
=== Debian ===
 +
[[Debian 8]],
 
[[Installation on Debian Lenny|Debian Wheezy]],  
 
[[Installation on Debian Lenny|Debian Wheezy]],  
 
[[Installation on Debian Lenny|Debian Squeeze]],  
 
[[Installation on Debian Lenny|Debian Squeeze]],  
 
[[Installation on Debian Lenny|Debian Lenny]]
 
[[Installation on Debian Lenny|Debian Lenny]]
 
  
 
=== Fedora ===
 
=== Fedora ===
 +
[[Fedora 25 Server]],
 +
[[Fedora 24 Server]],
 
[[Fedora 23 Server]],  
 
[[Fedora 23 Server]],  
 
[[Fedora_21_Server|Fedora 21 Server]],  
 
[[Fedora_21_Server|Fedora 21 Server]],  
Fedora 14,
 
 
[[Installation on Fedora 13|Fedora 13]],  
 
[[Installation on Fedora 13|Fedora 13]],  
Fedora 11,
+
[[Installation on Fedora 8| Fedora 8]],
Fedora 10,
 
Fedora 9,
 
[[Installation on Fedora 8| Fedora 8]],  
 
Fedora 7
 
 
 
  
 
=== RHEL ===
 
=== RHEL ===
Line 57: Line 112:
  
 
=== Ubuntu ===
 
=== Ubuntu ===
[[Ubuntu 14.04|Ubuntu 14.10]] <span style="background-color:Yellow;"><span style="color:Black">(Buggy)</span></span>,
+
[[Ubuntu 16.04]]
[[Ubuntu 14.04]],  
+
(<font color="red">obsolete, just for the archive:</font> [[Ubuntu 14.04]],  
 
[[Ubuntu 12.04|Ubuntu 13.10]],  
 
[[Ubuntu 12.04|Ubuntu 13.10]],  
 
[[Ubuntu 12.04|Ubuntu 13.04]],  
 
[[Ubuntu 12.04|Ubuntu 13.04]],  
Line 69: Line 124:
 
Ubuntu 8.10,  
 
Ubuntu 8.10,  
 
Ubuntu 8.04,  
 
Ubuntu 8.04,  
[[Installation on 7.10|Ubuntu 7.10]]
+
[[Installation on 7.10|Ubuntu 7.10]])
 
 
  
 
== Virtualization ==
 
== Virtualization ==
FOG can be used on bare metal as well as in most virtual server and client setups. Some of the virtualization techniques are really great when used with FOG, e.g. snapshots. Some people use virtualization to prepare and upload their "golden (master) images" all on one central location/server. Again like with the server OS we don't prefer any of the following or others that are out there. This is only a collection of hints and tricks plus maybe issues we know about.
+
FOG can be used on bare metal as well as in most virtual server and client setups. Some of the virtualization techniques are really great when used with FOG, e.g. snapshots. Some people use virtualization to prepare and capture their "golden (master / reference) images" all on one central location/server. Again like with the server OS we don't prefer any of the following or others that are out there. This is only a collection of hints and tricks plus maybe issues we know about.
  
 
=== Hyper-V ===
 
=== Hyper-V ===
Line 106: Line 160:
 
  sudo tunctl -t tap0 -u <username>
 
  sudo tunctl -t tap0 -u <username>
 
  sudo ifconfig tap0 x.x.x.x netmask 255.255.255.0 up
 
  sudo ifconfig tap0 x.x.x.x netmask 255.255.255.0 up
 +
 
  # generate disk image file
 
  # generate disk image file
 
  qemu-img create -f qcow2 hd.qcow2 10G
 
  qemu-img create -f qcow2 hd.qcow2 10G
 +
 
  # start VM using QEMU emulator (BIOS mode)
 
  # start VM using QEMU emulator (BIOS mode)
 
  qemu -m 512 -boot n -net nic,vlan=1 -net tap,vlan=1,ifname=tap0,script=/bin/true -hda hd.qcow2
 
  qemu -m 512 -boot n -net nic,vlan=1 -net tap,vlan=1,ifname=tap0,script=/bin/true -hda hd.qcow2
 +
 
  # start VM using real KVM virtualization (BIOS mode)
 
  # start VM using real KVM virtualization (BIOS mode)
 
  kvm -m 512 -boot n -net nic,vlan=1,macaddr=00:00:00:00:00:05 -net tap,vlan=1,ifname=tap0,script=/bin/true -hda hd.qcow2
 
  kvm -m 512 -boot n -net nic,vlan=1,macaddr=00:00:00:00:00:05 -net tap,vlan=1,ifname=tap0,script=/bin/true -hda hd.qcow2
 +
 
  # start VM as UEFI machine - as well using the more modern '-netdev' parameter
 
  # start VM as UEFI machine - as well using the more modern '-netdev' parameter
 
  kvm -m 512 -boot n -bios /usr/share/ovmf/OVMF.fd -device virtio-net-pci,netdev=hn0 -netdev tap,id=hn0,ifname=tap0,script=/bin/true -hda hd.qcow2
 
  kvm -m 512 -boot n -bios /usr/share/ovmf/OVMF.fd -device virtio-net-pci,netdev=hn0 -netdev tap,id=hn0,ifname=tap0,script=/bin/true -hda hd.qcow2
Line 131: Line 189:
 
After that the installer should run through like it would installing on bare metal or any other virtual environment!
 
After that the installer should run through like it would installing on bare metal or any other virtual environment!
  
'''Wake on LAN'''
+
'''Wake on LAN:'''
  
 
To be able to send WOL and multicast packages the container needs a proper MAC address. This is only the case if you configure the container to use a network bridge (veth instead of venet!).
 
To be able to send WOL and multicast packages the container needs a proper MAC address. This is only the case if you configure the container to use a network bridge (veth instead of venet!).
 +
 +
=== LXC ===
 +
One of the main things is to get NFS to work within LXC containers. While it used to be easy in Proxmox newer versions make it more complicated.
 +
 +
Proxmox 6.x: https://forums.fogproject.org/topic/15176/fog-server-in-lxc-container-under-proxmox-6
 +
 +
Proxmox 5.x: An update (around 23th of October 2018) broke NFS in LXC containers. Find a fix here: https://forum.proxmox.com/threads/mounting-nfs-in-lxc-not-working-since-latest-update.47815/
 +
 +
Proxmox 4.x: https://forums.fogproject.org/topic/7978/fog-in-lxc-container-how-to-configure-nfs-server
  
 
=== VirtualBox ===
 
=== VirtualBox ===
Bridged network, host only. Older versions have (PXE?) bug - Tom knows about that.
+
Bridged network or host only.
 +
 
 +
Most versions seem to suffer from a bug where iPXE would only be able to get an IP from the DHCP if started cold (vs. reboot).
 +
 
 +
This can be fixed by changing the iPXE binary from <code>undionly.kkpxe</code> to <code>ipxe.pxe</code> in the DHCP server config.
  
 
=== VMWare ESXi ===
 
=== VMWare ESXi ===
Line 142: Line 213:
  
 
* Create VM as normal.
 
* Create VM as normal.
 +
* Choose network adapter other than VMX3 (e.g. e1000) as we have seen [https://forums.fogproject.org/topic/7108/fog-bzimage-failing-to-load-after-pxe-boot loading issues] with those virtual adapters.
 
* Open VM Console, start up the VM. Press F2 on Boot Logo to enter BIOS.
 
* Open VM Console, start up the VM. Press F2 on Boot Logo to enter BIOS.
 
* Scroll over to boot tab, use + key to move Network boot to the top of the boot order.
 
* Scroll over to boot tab, use + key to move Network boot to the top of the boot order.
Line 163: Line 235:
  
 
== Security ==
 
== Security ==
Firewalld
 
iptables
 
SELinux
 
  
 +
[[FOG security]]
  
 
== Troubleshooting ==
 
== Troubleshooting ==
 
IMPORTANT, what to do when the installer fails? Where are the logs?
 
IMPORTANT, what to do when the installer fails? Where are the logs?
 +
 +
{{:Troubleshoot FOG}}

Latest revision as of 12:23, 19 May 2021

Requirements

Before diving right into the installation of FOG you need to decide which server OS you are going to use. FOG is made to install on RedHat based distro CentOS, Fedora, RHEL amongst others as well as Debian, Ubuntu and Arch Linux. Choose whichever you like most and have knowledge about! FOG is known to work with any of the above noted systems. Many installation manuals are available.

This listing is for informational purposes only, as the required components will be automatically downloaded and installed by the FOG installation script: PHP 5/7, MySql 5+/MariaDB 10+, Apache 2+, DHCP (pretty much any!), TFTP, FTP, NFS

The LAMP setup can also be easily adjusted for a "WAMP (Windows Apache MySQL PHP) system" though will require a bit more knowledge of what packages to use and how to integrate with the FOG system.

Please choose the distribution you have the most knowledge about, but the below list has the best support in FOG 1.3.0 right now. This list is by no means an absolute list to follow, though.

  • Ubuntu 16 or higher
  • Debian 8 or higher
  • CentOS 7 or higher
  • Red Hat 6 or higher
  • Fedora 22 or higher
  • Any version of Arch.

Download FOG

Please see: Getting_FOG

Installer

The FOG installer comes as a complex shell script that will handle all the package installs and configuring the services for you. It must be run as root (sudo works as well) to be able to set things up properly. Running the installer on a new system for the first time it will ask you a couple of questions regarding your network configuration and services you want to install.

Modes

FOG can be installed in two different modes. First is the normal FOG server which does all of the work. Choose this option if you only want have a single FOG server in your network. The second option is to install a FOG storage node which will serve as a second place to store images on and serve images to more clients (when doing unicast). Here you can find some more information about the two modes.

  FOG Server installation modes:
      * Normal Server: (Choice N) 
          This is the typical installation type and
          will install all FOG components for you on this
          machine.  Pick this option if you are unsure what to pick.

      * Storage Node: (Choice S)
          This install mode will only install the software required
          to make this server act as a node in a storage group

Command line options

The FOG installer has quite a few command line options. See the output below. You might want force FOG to setup the web interface via HTTPS, change the default PXE boot file or web root directory.

./installfog.sh --help
Usage: ./installfog.sh [-h?dEUuHSCKYXTFA] [-f <filename>] [-N <databasename>]
		[-D </directory/to/document/root/>] [-c <ssl-path>]
		[-W <webroot/to/fog/after/docroot/>] [-B </backup/path/>]
		[-s <192.168.1.10>] [-e <192.168.1.254>] [-b <undionly.kpxe>]
	-h -? --help			Display this info
	-o    --oldcopy			Copy back old data
	-d    --no-defaults		Don't guess defaults
	-U    --no-upgrade		Don't attempt to upgrade
	-H    --no-htmldoc		No htmldoc, means no PDFs
	-S    --force-https		Force HTTPS for all comunication
	-C    --recreate-CA		Recreate the CA Keys
	-K    --recreate-keys		Recreate the SSL Keys
	-Y -y --autoaccept		Auto accept defaults and install
	-f    --file			Use different update file
	-c    --ssl-path		Specify the ssl path
	               				defaults to /opt/fog/snapins/ssl
	-D    --docroot			Specify the Apache Docroot for fog
	               				defaults to OS DocumentRoot
	-W    --webroot			Specify the web root url want fog to use
	            				(E.G. http://127.0.0.1/fog,
	            				      http://127.0.0.1/)
	            				Defaults to /fog/
	-B    --backuppath		Specify the backup path
	      --uninstall		Uninstall FOG
	-s    --startrange		DHCP Start range
	-e    --endrange		DHCP End range
	-b    --bootfile		DHCP Boot file
	-E    --no-exportbuild		Skip building nfs file
	-X    --exitFail		Do not exit if item fails
	-T    --no-tftpbuild		Do not rebuild the tftpd config file
	-F    --no-vhost		Do not overwrite vhost file
	-A    --arm-support		Install kernel and initrd for ARM platforms

.fogsettings

Full article on the .fogsettings file can be found here: .fogsettings

Backups

TBD

Errorlog

TBD

Installation manuals

CentOS

CentOS 7, CentOS 6.4 (CentOS 6.5 also works), CentOS 5.3 (CentOS 5.4 & 5.5 also covered)


Debian

Debian 8, Debian Wheezy, Debian Squeeze, Debian Lenny

Fedora

Fedora 25 Server, Fedora 24 Server, Fedora 23 Server, Fedora 21 Server, Fedora 13, Fedora 8,

RHEL

TBA


Ubuntu

Ubuntu 16.04 (obsolete, just for the archive: Ubuntu 14.04, Ubuntu 13.10, Ubuntu 13.04, Ubuntu 12.10, Ubuntu 12.04, Ubuntu 11.04, Ubuntu 10.10, Ubuntu 10.04, Ubuntu 9.04, Ubuntu 8.10, Ubuntu 8.04, Ubuntu 7.10)

Virtualization

FOG can be used on bare metal as well as in most virtual server and client setups. Some of the virtualization techniques are really great when used with FOG, e.g. snapshots. Some people use virtualization to prepare and capture their "golden (master / reference) images" all on one central location/server. Again like with the server OS we don't prefer any of the following or others that are out there. This is only a collection of hints and tricks plus maybe issues we know about.

Hyper-V

Using the New VM Wizard:

Ensure the virtual switch your VM is connected to has a route to FOG!

Create VM Wizard > Installation Options: Select "Install an operating system from network-based installation server"


Existing VM:

Ensure the virtual switch your VM is connected to has a route to FOG!

Right click VM > Settings > BIOS

Move "Network Adapter" (sometimes labeled "Legacy Network Adapter") to the top of the boot order.


UEFI:

UEFI/Secure Boot is an option with Hyper-V on Server 2012 on Generation 2 VMs. It is enabled by default, and can be disabled in VM Settings -> Firmware: Uncheck secure boot.

Thanks to moses

KVM/QEMU

Can be used as kind of a lightweight desktop virtual environment to test FOG and master your images. Using this on the laptop as local test environment. Search forums and wiki but there is no valuable information about anyone using FOG on a KVM server. Asked user mxc as he seams to use it. Otherwise this will be a brief description on how to use this as I do it.

# setup network tap device as kind of a local software switch to connect it all
sudo tunctl -t tap0 -u <username>
sudo ifconfig tap0 x.x.x.x netmask 255.255.255.0 up

# generate disk image file
qemu-img create -f qcow2 hd.qcow2 10G

# start VM using QEMU emulator (BIOS mode)
qemu -m 512 -boot n -net nic,vlan=1 -net tap,vlan=1,ifname=tap0,script=/bin/true -hda hd.qcow2

# start VM using real KVM virtualization (BIOS mode)
kvm -m 512 -boot n -net nic,vlan=1,macaddr=00:00:00:00:00:05 -net tap,vlan=1,ifname=tap0,script=/bin/true -hda hd.qcow2

# start VM as UEFI machine - as well using the more modern '-netdev' parameter
kvm -m 512 -boot n -bios /usr/share/ovmf/OVMF.fd -device virtio-net-pci,netdev=hn0 -netdev tap,id=hn0,ifname=tap0,script=/bin/true -hda hd.qcow2

OpenVZ

OpenVZ (possibly within Proxmox) is mostly used to run the FOG server in a light weight kind of virtual environment. As OpenVZ is in nature similar to a chrooted environment you cannot actually PXE boot such a container. To install FOG as a server in OpenVZ you need to have NFS support on the host machine first and then add it to the container as well:

$ lsmod | grep nfsd
nfsd                  312315  14
$ grep nfsd /proc/filesystems
nodev   nfsd

If you don't see the kernel module nfsd loaded you might need to install the nfs-kernel-server package and load the module (usually done by the nfs-kernel-server init script). As mentioned before you need to enable access to nfsd from within the container you want to install FOG to:

$ vzctl stop $CONTAINER_ID
$ vzctl set $CONTAINER_ID --feature  nfsd:on --save
$ vzctl start $CONTAINER_ID

After that the installer should run through like it would installing on bare metal or any other virtual environment!

Wake on LAN:

To be able to send WOL and multicast packages the container needs a proper MAC address. This is only the case if you configure the container to use a network bridge (veth instead of venet!).

LXC

One of the main things is to get NFS to work within LXC containers. While it used to be easy in Proxmox newer versions make it more complicated.

Proxmox 6.x: https://forums.fogproject.org/topic/15176/fog-server-in-lxc-container-under-proxmox-6

Proxmox 5.x: An update (around 23th of October 2018) broke NFS in LXC containers. Find a fix here: https://forum.proxmox.com/threads/mounting-nfs-in-lxc-not-working-since-latest-update.47815/

Proxmox 4.x: https://forums.fogproject.org/topic/7978/fog-in-lxc-container-how-to-configure-nfs-server

VirtualBox

Bridged network or host only.

Most versions seem to suffer from a bug where iPXE would only be able to get an IP from the DHCP if started cold (vs. reboot).

This can be fixed by changing the iPXE binary from undionly.kkpxe to ipxe.pxe in the DHCP server config.

VMWare ESXi

Running a FOG client within an ESXi server is pretty close to what you would do on a bare metal machine:

  • Create VM as normal.
  • Choose network adapter other than VMX3 (e.g. e1000) as we have seen loading issues with those virtual adapters.
  • Open VM Console, start up the VM. Press F2 on Boot Logo to enter BIOS.
  • Scroll over to boot tab, use + key to move Network boot to the top of the boot order.

You can also do an on-demand network boot by hitting F9 on startup, if you don’t want to change the boot order permanently.

UEFI:

UEFI is disabled by default for VMs in ESXI 6.0+. To enable it for a VM, go to VM Settings > Options Tab > Advanced: Boot Options and change the boot firmware from BIOS to EFI.

Thanks to moses

VMWare Player

Is this still in use?? Don't care if there is nothing about it in wiki or forums!

Xen/XenServer

See forums

Security

FOG security

Troubleshooting

IMPORTANT, what to do when the installer fails? Where are the logs?

Below, you will find a listing of all FOG troubleshooting related articles.

Debug Mode

Is PC compatible with FOG kernel

Troubleshoot TFTP

Troubleshoot FTP

Troubleshoot NFS

Troubleshoot MySQL

Troubleshoot Downloading - Multicast

Multicast

Multicasting

Troubleshoot Downloading - Unicast

Troubleshooting an image push to a client

Troubleshoot Web Interface

Active Directory - FOG Setting

The time in the logs and dashboard are off

PXE error code

Password Central

Error Messages

Uninstalling FOG Service on WinXP clients

Boot looping and Chainloading

Setting up and building UDPCast...Failed!

Troubleshooting_an_image_push_to_a_client

Looking at the network packets using tcpdump and wireshark