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Ekiga registration error: Loop Detected

Today we cannot connect an Ekiga client to our Asterisk SIP server.
The error reported by Ekiga was “loop detected” (with a poor italian translation “rilevato ciclo”).
We found a solution by Asterisk CLI command “sip set debug on” and by inspecting the debugging log: Ekiga sends packets with a wrong address in class assigned to eth0 (without cable) by DHCP.
As reported by RFC is the “link local” block.
It was set aside for this special use in the Standards Track document, RFC 3927 and was further documented in the Best Current Practice RFC 5735. It is allocated for communication between hosts on a single link. Hosts obtain these addresses by auto-configuration, such as when a DHCP server cannot be found.
RFC specify that a router MUST NOT forward a packet with an IPv4 Link-Local source or destination address, and so Ekiga shouldn’t send a SIP packet with this kind of address.
Anyway, to resolve this problem, stop dhcp on a disconnected interface or remove this assigned address.

KVM virtualization with Debian GNU/Linux in 7 steps

1. Install required packages

# apt-get install bridge-utils kvm

2. Create an empty kvm virtual machine image:

# kvm-img create vm.qcow2 -f qcow2 20G

3. Prepare a bridge so you can attach to it the net interface of your vm.

3a. Setup your eth0 interface to capture all the traffic:

# ifconfig eth0 promisc up

3b. Create the bridge interface:

# brctl addbr br0

3c. Put your eth0 interface in the bridge (so it captures all the wire traffic and sends it to all the others interfaces in the bridge and vice-versa):

# brctl addif br0 eth0

4. Restore your network connection by the br0 interface (optional)

4a. Bring up your bridge interface and give to it an address (so you can use it as your ip address):

# ifconfig br0 <your_ip> <your_netmask> up

4b. Remember to restore your default gateway:

# ip route add default via <gateway_ip>

5. Start your virtual machine (-boot d to install Debian from the ~/iso/debian.iso image, optional)

# kvm -hda vm.qcow2 -cdrom ~/iso/debian.iso -boot d -net nic,vlan=0 -net tap,vlan=0,ifname=tapvm

6. Add tap interface of vm to your bridge

# brctl addif br0 tapvm

7. Enable forwarding and tell to iptables to allow tapvm traffic to flow through your pc

# sysctl -w net.ipv4.ip_forward=1
# iptables -A FORWARD -m physdev --physdev-out tapvm -j ACCEPT
# iptables -A FORWARD -m physdev --physdev-in tapvm -j ACCEPT

Debian Release Party!

Thank you Debian!
Welcome Wheezy!!! 😀

Thank you Debian!

Thank you Debian!

Thank you Debian!

Thank you Debian!

Incendio Sala UPS Aruba DOWN – Tempi di ripristino

Purtroppo la sala batterie di Aruba ha subito un principio di incendio e per questo tutti i servizi sono stati disattivati (Aruba e tutti i servizi collegati sono down). Secondo le loggate del mio server in housing su Aruba il down è iniziato alle 4.39 circa.

Poco fa sono riuscito a mettermi in contatto con il team di Aruba che attualmente risulta down.
Hanno confermato i primi interventi tecnici specializzati nel primo pomeriggio ed il conseguente graduale riavvio dei servizi nella nottata.

Il canale “ufficiale” di Aruba per avere informazioni aggiornate:!/arubait