We always want to prefer the unique node address for outgoing traffic. Note
that this doesn't have an effect with batman-adv, as usually br-client will
be the outgoing interface, so the unique address would be chosen anyways.
macvlan interfaces never directly exchange traffic with the underlying
interface, but only with other hosts behind the interface. In consequence,
router advertisements from the uradvd running on br-client could never
reach local-node, preventing it from getting an IPv6 address without RAs
from an external radvd. Fix this be replacing the macvlan interface with
a veth pair (with the peer interface in br-client).
As a side effect, this saves about 5KB of flash, as the veth module is
simpler than macvlan.
When preparing the migration from macvlan to veth for local-node, MAC
address conflicts occurred as some ports of br-client had the same address
as local-node. Reverting the roles of both interfaces fixes this.
By default, br-client is left as an interface without addresses and
firewall rules that drop everything, so the bridge is used to connect its
ports only. gluon-mesh-batman-adv-core changes this to the usual set
of addresses and firewall rules.
The batadv debugfs requires large memory blocks to write the text debug
tables. This is inefficient for large tables like the global translation
table or the originators table.
The memory requirement can be reduced by using netlink. It copies smaller
packets in a binary format to the userspace program. The respondd module of
gluon-mesh-batman-adv-core can therefore parse larger originator tables
without causing an OOM on systems which are tight on memory.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
The batadv debugfs requires large memory blocks to write the text debug
tables. This is inefficient for large tables like the global translation
table or the originators table.
The memory requirement can be reduced by using netlink. It copies smaller
packets in a binary format to the userspace program. gluon-status-page-api
can therefore parse larger originator tables without causing an OOM on
systems which are tight on memory.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
MAC and IP addresses are switched. This makes the gluon-client-bridge
package more useful for different routing protocols that don't need a
unique address on the client bridge.
As a side effect, gluon-radvd is now using the next-node address, which had
been considered before, but was dismissed to avoid having gluon-radvd
depend on gluon-next-node and gluon-mesh-batman-adv. This will be useful
for announcing default routes via gluon-radvd.
One downside is that this introduces a minor dependency on batman-adv in
gluon-respondd: the hotplug script that checked for the client interface
before will now check for local-node. This doesn't really matter: for mesh
protocols without a local-node interface, the check will do nothing (which
makes sense, as there is no interface to bind to for mesh-wide respondd).
Because we unconditionally appended `-i br-client` to the command line of
respondd, it wasn't restarted when br-client changed state. Now, we use a
jsonfilter expression on the network.interface dump data, similar to how the
other interface names are generated, and only add the interface to the argument
list if it is up.
If cookies are disabled, the Statuspage only displays an empty ("Not connected")
This checks if the localStorage API is available and working and only uses it in this case
Also allows better backwards compatibility.
Users may have defined additional mesh interfaces. Properly migrate these
to avoid subtly breaking the network config (and make them ready for new
mesh protocols).
Switch to:
1. WAN
2. LAN
3. Mesh VPN
As WAN and LAN are setup in gluon-mesh-batman-adv-core (and will be moved
to gluon-core), while the mesh VPN has its own package, giving WAN and LAN
the first indices is preferable.
Just like we enabled multicast snooping on the batman-adv client bridge
again, let's do the same for the WAN side.
With one exception: The IGMP/MLD querier is kept disabled to avoid
becoming too "bossy"/"noisy" on a foreign network. The main router on
the WAN side should perform querying and by that enable
IGMP/MLD/snooping if it considers this appropriate there.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
A few issues with the bridge snooping were identified and fixed
upstream in OpenWRT:
* "firewall: Allow IGMP and MLD input on WAN" (r45613)
* "kernel: bridge: backport two snooping related patches" (r45783)
* netifd: "bridge: Fix multicast_to_unicast feature by hairpin+isolate"
(OW: "netifd: update to the latest version, adds multicast-to-unicast fixes" (r46719))
* "kernel: bridge, multicast-to-unicast: assign src after pskb_may_pull()" (r46721)
* "kernel: bridge, multicast-to-unicast: fix echoes on STA" (46765)
These have very likely caused issues with the bridge snooping before,
which led to disabling it in the past. Let's reenable the multicast
snooping now that they were fixed for reduced multicast overhead on the
wifi.
Advantages are the following:
This mildly reduces overhead on the mesh layer. And significantly reduces
overhead on the AP interface and therefore significantly increases
available airtime (the currently most significant scalability bottleneck).
Secondly removes an easy, often accidental node-local Denial-of-Service
vector based on multicast flooding / streaming.
Thirdly, makes node-local multicast streaming feasible.
Finally should noticably increase battery life of mobile devices.
Note: bridge querier is disabled for br-wan. We want to avoid becoming
too "bossy"/"noisy" on a foreign network.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
The mesh side has become fairly huge in many communities. Up to
a few thousand entries can currently be found in the forwarding
database (fdb) of a bridge for its bridge port bat0.
The bridge fdb is kind of redundant to the batman-adv global translation
table here. Therefore this patch tries to reduce memory footprint by
following an approach similar to the IGMP/MLD split patchset approach:
Make the bridge oblivious not only regarding multicast listeners towards
the mesh but with this patch unicast hosts on the mesh, too.
If the destination of an ethernet frame is known by the bridge to be a
local one, then the frame is forwarded to the according port. If it is
unknown, then the frame is forwarded to the wifi AP interface and bat0.
mac80211 and batman-adv then know whether to drop or forward a frame
further through their own book-keeping.
Note that unicast-flood is not disabled for the wifi AP bridge port, nor
is learning disabled on the wifi AP. This is mainly to keep the
configuration in UCI and according setup scripts simple ;). However, not
disalbling unicast-flood on the wifi AP interface might also give a
minor latency improvement for newly joining wifi clients.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
The arguments are now provided by gluon-mesh-batman-adv-core, so
gluon-radvd can be used with other mesh protocols.
[Matthias Schiffer: removed PROVIDES dependency]
Some drivers (mt76) don't support arbitrary MAC addresses. Use the
addresses provided by the driver (avoiding the primary address) by default,
but fall back to our has-based scheme when the driver doesn't provide
(enough) addresses.
The new MR1750v2 device support is only available in LEDE master. The
relevant patches have to backported to add support for them in Gluon
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
The new OM2P-HSv3 device support is only available in LEDE master. The
relevant patches have to backported to add support for them in Gluon
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Most doubles that are delivered via respondd have limited input
precision, but are converted with up to 17 digits of precision. That can
cause ugly blowups like 0.2800000000000001 in the output, which is
avoided by specifying better format strings (like "%.2f" in most cases).
The OpenMesh devices have a sticker with the eth0 mac address on the
bottom. Also all other mac addresses are calculated based on this address.
Therefore, it is better to use this as primary mac address instead of the
WiFi mac address.
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
This patch adds a new gluon-ebtables package to filter IGMP/MLD messages
via ebtables.
For one thing this reduces multicast overhead: About one third of all
ICMPv6 multicast traffic in Lübeck or Hamburg is MLD.
Furthermore it removes a potential Distributed Denial-of-Service vector
(see Gluon ticket #553).
Finally, it is a prerequisite for enabling bridge multicast snooping in
a decentral and robust fashion.
Note that IGMP/MLD are filtered for multicast traffic coming from
the mesh, too (new MULTICAST_IN), as unfortunately there seem to
be other queriers somewhere in the mesh at least for Freifunk
Lübeck. Also adding these rules to be prepared to anyone intentionally
or unintentionally disabling these filters on his/her node.
Node operators not running Gluon (for instance gateway nodes) should
make sure to either enable multicast_router towards bat0 or disable
multicast snooping entirely if they have a bridge on top of bat0.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
ebtables actually skips any IPv6 extension headers like the hop-by-hop
one. So this rule is actually void.
The intend back then was to allow passing MLD messages into the mesh.
Since extension headers are skipped, the general icmpv6 rule will
actually match MLD messages. So the hop-by-hop rule is unnecessary,
too.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Don't fork reboot process before all package hooks have been handled and
rendering is complete.
Replace debug.setfenv hack to close stdout with nixio.dup.
Fixes#772
The image validation currently fails on some devices (tested OpenMesh)
because it isn't done via sysupgrade. But the checks depend partially on
the integration in sysupgrade (e.g. via loops that can be stopped via
"break statements").
Instead of hacking its own version check, it is easier and better tested to
just use 'sysupgrade -T' like it is already done by LuCI.
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Lua's tables are 1-based, so we must decrement the index by 1 to get the
desired MAC addresses. By not doing this, the second IBSS interface would
get the address with index 8, but only indices 0..7 are available.
Fixes: c73a12e0ea
There are a few devices which have more than one LAN interface (for example
some revision of the TL-WR941ND, which uses a DSA-based switch, so each
switch port has its own netdev.) On these devices we need a bridge for
mesh-on-lan (as the alternative of adding them to batman-adv individually
would need too many MAC addresses.)
While ath9k/ath10k devices can supprt VIFs with any combination of MAC addresses, there are also adapters which have a hardware MAC filter which only allows a few bits to differ. This commit changes the addresses of all VIFs to ony differ in the last 3 bits, which is required to support many Ralink/Mediatek based WLAN adapters.
Technically, the new addresses are generated by calculating an MD5 hash of the primary MAC address and using a part of this hash as a prefix for the MAC addresses.
The addresses (BSSIDs) of the AP VIFs are also reused for the LAN and WAN interfaces in mesh-on-LAN/WAN mode to reduce the number of needed addresses, and thus reduce the chance of collisions. This is not a problem as the MAC addresses of the AP VIFs are never used except as BSSID, and thus not seen by routing protocols like batman-adv.
Fixes#648
[Matthias Schiffer: rewrote commit message]
Device information can be found at:
http://www.8devices.com/products/carambola-2https://wiki.openwrt.org/toh/8devices/carambola2
I only did some minimal testing of gluon on the carambola 2 development
board:
- Config mode works
- Connects to Wifi Mesh
- Allows clients to connect
Notably, autoupgrade has not yet been tested.
Change to 010-primary-mac is necessary as the mac address printed
on the sticker is the one of eth0, not the wifi mac.
We are mostly dealing with the 2.4GHz crap-band here, so increasing the
IGMP/MLD robustness parameter to three to be able to compensate for up
to two consecutive instead of just one lost packet.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
There are some devices not acting properly to roaming events, in that
they do not timely reissue IGMP/MLD reports after reconnecting.
To compensate for that this commit reduces the query interval from 125
seconds to 20 and the query response interval from 20 seconds to 5.
This reduces a timeout to 20+5 seconds in the worst-case (12.5s average)
after a roaming event for such broken devices. This should be below the
30s "impatient user threshold" and below any connection timeout.
Until the bridge multicast snooping + querier gets re-enabled this is a
no-op.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Adopt the according modifications to the default firewall settings of
the WAN interface from OpenWRT, revision 45613.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
An IGMP/MLD domain split will prevent us from being able to track
multicast listeners on other nodes.
Therefore we need to always hand any multicast packets we received from
local clients to batman-adv. With bridge multicast snooping disabled,
the current setting in Gluon, this is already the case.
However, in preparation to enabling multicast snooping, we need to
enforce forwarding towards batman-adv by setting the bridge port
option "multicast_router" to 2.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
It is not supported by all browsers yet.
Also change load display always to display 2 decimal digits (as it is read
from the kernel with 2 decimal digits).
Fixes#606
Mobile browsers will often show or hide the address bar while scrolling.
This causes resize events which would often reset the signal graphs.
Fixes#662
Ethernet links provide transitive connectivity in all but very unusual
setup, enable mesh_no_rebroadcast to reduce load for devices on links with
many nodes.
Fixes#652
This new feature introduces the new uci section 'gluon-core.wireless' with a preserve_channels option:
* preserve_channels (boolean)
By setting this option to 1 (true) wifi channels will be preserved during upgrades.
Instead of starting gluon-respondd from a hotplug handler, add a proper
init script. The new init script has a restart_if_running argument which
is now used by the hotplug handler.
introduce function to recurse down to the lowest layer-2 interface
corresponding to a given interface.
also re-introduce some of the previously removed input validation plus
some more to protect against glob and path based exploits.
The timeout was calculated incorrectly (in each iteration the span between
the start time and the current time was substracted from the timeout
again), and would often become negative, causing warnings in the kernel
log.
On the status page statistics section counters for transmitted and received traffic were mixed up. Transmitted traffic was shown as received while received traffic was shown as being transmitted.
Fixes#586
Is makes sense to always look for both ibss_radio* and mesh_radio* sections
to determine if the meshing should be enabled when regenerating these
sections. Doing this, the disabled state will survive updates changing the
section name (either updating from pre-2015.2 while keeping IBSS, or
changing from IBSS to 11s or vice-versa).
If both ibss_radio* and mesh_radio* sections exist, the disabled state will
be kept correctly for each section, the behaviour is changed only when
creating a section that didn't exist before.
Fixes#549
PKG_FILE_DEPENDS caused the whole site repo to be hashed to determine if
gluon-site needed rebuilding. While this is normally no problem,
alternative build setups sometimes put the Gluon repo inside the site repo,
causing long build times and parallel build failures.
in a layer 2 mesh network, multicast pings cause a lot of traffic in the
network, significantly increasing the 'backgroudn noise' (= Grundrauschen)
and stressing nodes in the network.
this commit blacklists all icmpv4 multicast traffic as well as multicast
icmpv6 echo-requests and node iformation queries. as no application
depending on these types of multicast traffic is known, blacklisting is safe.
gluon-radio-config contained only a single file. The code has been adjusted
to allow creating a Gluon configuration without WLAN support by removing
the wifi24 and wifi5 sections from site.conf.
The file promotes the probably unnecessary re-execution of the announce
scripts. Instead, gluon-announced should be queried using
gluon-neighbour-info -d ::1 -p 1001 -t0 -r nodeinfo
if both gluon-announced and gluon-neighbour-info are present. But to not
depend on any of those, no script for this one-liner is provided.
Now that the status page api has been rewritten in C CPU load and memory
usage is much lower. Also, nodes with both ibss and 11s mesh and dual
band wifi may require up to 9 connections for a single client, thus the
previous limit of 12 seemed a little low.
Convert option ifname in br-client to use a list instead. This
simplifies adding and remove interfaces:
uci:add_to_set("network", "client", "ifname", "eth0")
uci:remove_from_set("network", "client", "ifname", "eth0")
An option ifname will be automatically converted to a list when
performing an upgrade.
Packages affected: gluon-mesh-batman-adv-core, gluon-luci-portconfig
When rebooting the node in config mode, currently the fastd key is
forcefully displayed in a fixed format. This is confusing in communities
where fastd accepts all keys and no key submission is needed.
Furthermore, some communities might want to personalize the display of
the key (see #387).
This patch moves the displaying <div> from the package's lua file to the
translation files of the sample site configuration and mentiones the
change in the release notes.
Apart from replacing a patch for the former by two patches for latter,
this involved minimal adaptations of the lua scripts in the following
packages:
* gluon-announce
* gluon-announced
* gluon-mesh-batman-adv-core
* gluon-status-page
Split basic radio configuration from gluon-mesh-batman-adv as this will
be required for virtually any wireless mesh protocol.
This package takes care of setting:
- wireless channel,
- htmode and
- regulatory domain
gluon-mesh-batman-adv-core depends on this package.
This is a site.conf-breaking change in regard to the wireless config.
Make sure to read http://gluon.readthedocs.org/en/latest/user/site.html
and update your site.conf accordingly!
Support for 802.11s mesh interfaces has been added. Gluon now supports
three interface types: ap, ibss and mesh. All of them are now optional
and may be configured independently in site.conf.
A sample site.conf may look like this:
wifi24 = {
channel = 1,
htmode = 'HT40+',
ap = {
ssid = 'luebeck.freifunk.net',
},
ibss = {
ssid = '02:d1:11:37:fc:38',
bssid = '02:d1:11:37:fc:38',
mcast_rate = 12000,
},
mesh = {
id = 'ffhl-mesh',
mcast_rate = 12000,
},
},
The nodeinfo/network/addresses announcement included deprecated and
tentative addresses, which it clearly shouldn't as the host doesn't want
to be contacted on those addresses. They are now filtered out.
Always output empty objects or nothing at all where objects are expected, but
no elements exist.
Also remove a few unneeded "requires", a few basic modules are provided by
announce.lua by default.
By introducing a new option -a in addition to -p this patch allows
controlling the on-link flag of announcements.
A prefix specified using -a will have the on-link flag set to zero
while a prefix specified using -p will retain its behaviour (i.e.
on-link flag set).
Example:
gluon-radvd -i local-node -p 2001:db8:aaaa:/64 -a 2001:db8:bbbb::/64
This will announce 2001:db8:aaaa::/64 with the on-link flag set and
2001:db8:bbbb::/64 with the flag unset.
This adds mesh_on_lan functionality.
A new optional site.conf option, mesh_on_lan, has been added. If set to
'true', all LAN ports will be used for meshing instead of being part of
the client bridge.
This will introduce a new nodeinfo object, network.mesh.bat0.interfaces,
containing any of the the following subordinated objects:
- wireless
- tunnel
- other
Each of these objects contains a (possibly empty) list of MAC addresses
(lowercase, colon-notation) corresponding to a interface of the given
class. Combined with a batman graph it is thus possible to mark
sub-graphs as "wireless" or "vpn".
The previously used object mesh_intefaces is superseded by this new
object structure and mesh_interfaces will be removed in a future Gluon
release.
OpenWrt doesn't set the regdom unless a WLAN device is started. Explicitly set
the regdom in the setup mode to get the correct list of allowed txpower entries
in the planned LuCI module.
In Bremen it has been noted that a prefix may lead people to believe it
has to stay there and thus naming their nodes "ffhb-*", which is not
what the community wants (see FreifunkBremen/gluon-site-ffhb#1).
However, an empty prefix lead to the connecting hyphen still being
inserted. This commit thus makes the hyphen part of the configured
prefix and allows the prefix to be missing from the `site.conf`.
This adds a new announce.d datum "neighbours" (alfred 160) containing
information about mesh neighbours. It's intended to be an replacement
for batadv-vis.
In addition to the data already provided by batadv-vis it'll also
provide information about direct wifi neighbours.
Unlike batadv-vis, no data about clients is transmitted.
Sample data:
{
"wifi": {
"90:f6:52:82:06:02": {
"neighbours": {
"f8:d1:11:2c:a7:d2": {
"noise": -95,
"inactive": 0,
"signal": 0
},
"96:f6:52:ff:cd:6f": {
"noise": -95,
"inactive": 0,
"signal": -37
}
}
}
},
"batadv": {
"90:f6:52:82:06:02": {
"neighbours": {
"96:f6:52:ff:cd:6f": {
"lastseen": 2.8500000000000001,
"tq": 177
}
}
},
"90:f6:52:82:06:03": {
"neighbours": {
"f8:d1:11:2c:a7:d3": {
"lastseen": 2.3500000000000001,
"tq": 206
}
}
}
},
"node_id": "90f652820602"
}
Moving the scripts to a common directory not only vastly simplifies the
zzz-gluon-upgrade script, but also allows to define an ordering of such
scripts across packages.
add invariant script "001-node-system" to add section "system" if not exist; add invariant script "010-node-role"
to add section "system" if not exist; add invariant script "010-node-role" to set role to default value
(site.roles.default) if not exist; depends on new site.conf section
When an early reboot is triggered because an upgrade script has disabled the
config mode, we need to explicitly call /etc/init.d/done, otherwise the overlay
will not be finalized after a firstboot and we get an endless reboot loop.
the gluon-announced package installs a hotplug script
that uses announce.lua from the gluon-announce package.
So we need to include gluon-announce as dependency.
Signed-off-by: flokli <florian@darmstadt.freifunk.net>
the ports were interchanged, see the following packet flow:
client:546 --> [ff02::1:2]:547
server:547 --> client:546
therefore we need to allow outgoing multicast packets with dst-port 547
and unicast packets from bat0 to clients with dst-port 546 and 547 in the other direction
This package will run as invariant script after each upgrade and copy
all keys from site.conf's authorized_keys entry to
/etc/dropbear/authorized_keys.
Existing keys will be preserved.
The site.conf entry 'authorized_keys' is required (if this package is
selected) and must contain a list of strings, each representing a line
of the resulting file.
Using the line
```
* * * * echo "foobar"
```
(notice the missing fifth time field) in a crontab causes gluon-cron
to enter an endless loop while parsing it, thus it won't even execute
the other, valid crontabs.
This is caused by the loop in [line 138] where `begin - min`
substracts the unsigned `min` from the signed `begin`. If now `begin`
is invalid, `strict_atoi` returns -1 and the loop starts at
`(-1)-1=MAX_INT` and runs while `i <= MAX_INT` which is always true.
The real culprit lies in [line 134] where exactly this case
`begin < min` is checked - but because of the signedness, this check doesn't
work as expected either.
The easiest solution is to make `min` a signed integer instead of an unsigned
one, as we do not require it to be very large and only pass the constants 0 or
1 to it.
To avoid other similar problems, this patch makes the input variable `n` a
signed integer as well.
Since switching to Barrier Breaker/procd, we'd not notice if we were
upgrading from a version before renaming the config file to gluon-setup-mode
as the upgrade scripts run after the preinit.
Fix this by checking later during setup mode init again and rebooting into the
regular run mode if we detect this case.
Die Bezeichnung "Mesh-VPN" ist etwas irreführend. Man kann denken, dass hiermit das Meshing aktiviert wird, wobei es ja — im Gegenteil — um eine Nutzung des WAN geht.
This adds
"client" { "total": <int>, "wifi": <int>" }
to statistics.d. "total" will be the number of clients connected.
"wifi" will be the number of clients connected over wifi. I.e. "total"
will always be equal to or greater than "wifi".
The node will not count itself.
This commit splits gluon-config-mode into several, mostly independent
packages.
* gluon-config-mode-core: basic functionality (required)
* gluon-config-mode-hostname: hostname field
* gluon-config-mode-autoupdater: show when autoupdater is enabled
* gluon-config-mode-mesh-vpn: fastd vpn configuration, bw limit
* gluon-config-mode-geo-location: geo coordinates
* gluon-config-mode-contact-info: contact info field
The package gluon-config-mode has been removed. You need to replace
it with these packages (or any subset of them) in site.mk:
* gluon-config-mode-hostname
* gluon-config-mode-autoupdater
* gluon-config-mode-mesh-vpn
* gluon-config-mode-geo-location
* gluon-config-mode-contact-info
Note: It is not possible to deactivate the autoupdater in config mode
anymore (expert mode will still allow it). Instead, a message is shown
in case the autoupdater is enabled.
Previously, the config-mode was responsible for generating the fastd
secret. This patch sets the default secret to "generate" causing a
secret to be generated on its first use (e.g. show_key or start).
This also changes the info page (in Expert Mode) to show "n/a" when the
public key is not yet available.
This adds a `node_id` to announce.d. `node_id` is an hex-number uniquely
identifying a particular node. On nodes having a
primary MAC this MAC address will be used as `node_id` (sans the
colons). The value is opaque. It must not be converted back into
a MAC address.
`node_id` should be sent in all alfred and announced packets to
ensure clients can link the data to a particular node.
This is a simple daemon that will respond to multicast UDP packets
containing the keyword "nodeinfo" with all the information we
currently distribute using alfred.
The daemon will listen on all mesh interface, that is the hard
interfaces batman-adv uses.
This will make a node announce all MACs of its interfaces participating
in the batman-adv mesh. This enables other nodes to associate the
announced object with both the data reported by batadv-vis as well as a
simple list of neighbours as output by `iw dev $IFACE station dump`.
All announce.d scripts have been moved to /lib/gluon/announce/announce.d
The script /lib/gluon/announce/announce.lua will collect all information
and output json.
If the `monitor` attribute in the site.conf is defined, the cron
script is modifed to send debug informations, generated on bug
detection, to given remote host and port,
e.g.: "fda1:384a:74de:4242::2 8090"
