ICMP 435 Destination unreachable (Communication administratively filtered)
Hello, if the Switch sends requests can see only in wireshark this: ICMP 435 Destination unreachable (Communication administratively filtered) $ tshark -Y "ip.addr==192.168.1.0/24" Capturing on 'eth0' 109 12.985452883 192.168.1.78 → 172.16.1.28 RADIUS 407 Access-Request id=5 110 12.985550915 172.16.1.28 → 192.168.1.78 ICMP 435 Destination unreachable (Communication administratively filtered) 173 17.971115508 192.168.1.78 → 172.16.1.28 RADIUS 407 Access-Request id=5, Duplicate Request 174 17.971208619 172.16.1.28 → 192.168.1.78 ICMP 435 Destination unreachable (Communication administratively filtered) 205 22.971310597 192.168.1.78 → 172.16.1.28 RADIUS 407 Access-Request id=5, Duplicate Request 206 22.971388225 172.16.1.28 → 192.168.1.78 ICMP 435 Destination unreachable (Communication administratively filtered) 247 27.971195313 192.168.1.78 → 172.16.1.28 RADIUS 407 Access-Request id=5, Duplicate Request 248 27.971249900 172.16.1.28 → 192.168.1.78 ICMP 435 Destination unreachable (Communication administratively filtered) but in debug mode (raduisd -X) can see nothing. Listening on auth address * port 1812 bound to server default Listening on acct address * port 1813 bound to server default Listening on auth address :: port 1812 bound to server default Listening on acct address :: port 1813 bound to server default Listening on auth address 127.0.0.1 port 18120 bound to server inner-tunnel Listening on proxy address * port 49780 Listening on proxy address :: port 40915 Ready to process requests What did I wrong ? --------------- If I dow a local test with radtest I can see there something radtest <PC MAC Address> none localhost 10 testing123
On 11.08.21 11:50, Dennis Schneck wrote:
if the Switch sends requests can see only in wireshark this: ICMP 435 Destination unreachable (Communication administratively filtered)
110 12.985550915 172.16.1.28 → 192.168.1.78 ICMP 435 Destination unreachable (Communication administratively filtered)
This ICMP code is only generated when something like iptables or nftables is rejecting the packet. So check for any local firewalls active on your server and open the needed ports. Grüße, Sven.
Hi Sven, no firewall active: # iptables --list Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination On 11.08.21 12:14, Sven Hartge wrote:
On 11.08.21 11:50, Dennis Schneck wrote:
if the Switch sends requests can see only in wireshark this: ICMP 435 Destination unreachable (Communication administratively filtered)
110 12.985550915 172.16.1.28 → 192.168.1.78 ICMP 435 Destination unreachable (Communication administratively filtered)
This ICMP code is only generated when something like iptables or nftables is rejecting the packet.
So check for any local firewalls active on your server and open the needed ports.
Grüße, Sven.
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-- ---------- Mit freundlichen Grüßen / Best Regards / 诚挚的问候 Dennis Schneck Schuler Pressen GmbH | Schuler-Platz 1 | 73033 Göppingen | Germany Tel. +49 7161 66-2933 | Fax +49 7161 66-8440 Dennis.Schneck@schulergroup.com | http://www.schulergroup.com Member of the ANDRITZ Group | Follow us on social media Mandatory information for e-mails (acc. EHUG) | Information on Processing of our data: www. schulergroup.com/unternehmen/datenschutz/index.html
On 11/08/2021 11:17, Dennis Schneck wrote:
no firewall active:
There is a firewall, somewhere. If you used the wrong port you'd get port unreachable. If there's a firewall then you'll get admin prohibited (or possibly something else depending on how the firewall is set up). You didn't say where you are running wireshark. If it's on the RADIUS server, then the RADIUS server has the firewall (because you see the requests and the responses). If you are capturing elsewhere then something from the switch up to the RADIUS server has a firewall. -- Matthew
Hi Matthew,
You didn't say where you are running wireshark
On the Radius Server
If there's a firewall then you'll get admin prohibited (or possibly something else depending on how the firewall is set up).
on the Radius Server is no Firewall
If you are capturing elsewhere then something from the switch up to the RADIUS server has a firewall.
I can ask the colleage If he can capture on the switch and the PC behind the switch On 11.08.21 12:33, Matthew Newton wrote:
On 11/08/2021 11:17, Dennis Schneck wrote:
no firewall active:
There is a firewall, somewhere.
If you used the wrong port you'd get port unreachable.
If there's a firewall then you'll get admin prohibited (or possibly something else depending on how the firewall is set up).
You didn't say where you are running wireshark. If it's on the RADIUS server, then the RADIUS server has the firewall (because you see the requests and the responses). If you are capturing elsewhere then something from the switch up to the RADIUS server has a firewall.
-- ---------- Mit freundlichen Grüßen / Best Regards / 诚挚的问候 Dennis Schneck Schuler Pressen GmbH | Schuler-Platz 1 | 73033 Göppingen | Germany Tel. +49 7161 66-2933 | Fax +49 7161 66-8440 Dennis.Schneck@schulergroup.com | http://www.schulergroup.com Member of the ANDRITZ Group | Follow us on social media Mandatory information for e-mails (acc. EHUG) | Information on Processing of our data: www. schulergroup.com/unternehmen/datenschutz/index.html
On 11.08.21 12:17, Dennis Schneck wrote:
no firewall active:
# iptables --list Chain INPUT (policy ACCEPT) target prot opt source destination
Chain FORWARD (policy ACCEPT) target prot opt source destination
Chain OUTPUT (policy ACCEPT) target prot opt source destination
You also need to check for nftables: nft list ruleset Grüße, Sven.
hi sven, thanks OK good to know! disabled in yast the firewall now I can see the request ... but no response to the switch from the radius server.... On 12.08.21 10:09, Sven Hartge wrote:
On 11.08.21 12:17, Dennis Schneck wrote:
no firewall active:
# iptables --list Chain INPUT (policy ACCEPT) target prot opt source destination
Chain FORWARD (policy ACCEPT) target prot opt source destination
Chain OUTPUT (policy ACCEPT) target prot opt source destination
You also need to check for nftables:
nft list ruleset
Grüße, Sven. - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html
-- ---------- Mit freundlichen Grüßen / Best Regards / 诚挚的问候 Dennis Schneck Schuler Pressen GmbH | Schuler-Platz 1 | 73033 Göppingen | Germany Tel. +49 7161 66-2933 | Fax +49 7161 66-8440 Dennis.Schneck@schulergroup.com | http://www.schulergroup.com Member of the ANDRITZ Group | Follow us on social media Mandatory information for e-mails (acc. EHUG) | Information on Processing of our data: www. schulergroup.com/unternehmen/datenschutz/index.html
On 11/08/2021 10:50, Dennis Schneck wrote:
if the Switch sends requests can see only in wireshark this: ICMP 435 Destination unreachable (Communication administratively filtered)
$ tshark -Y "ip.addr==192.168.1.0/24" Capturing on 'eth0' 109 12.985452883 192.168.1.78 → 172.16.1.28 RADIUS 407 Access-Request id=5 110 12.985550915 172.16.1.28 → 192.168.1.78 ICMP 435 Destination unreachable (Communication administratively filtered) ... but in debug mode (raduisd -X) can see nothing.
What did I wrong ?
Firewall ("administratively filtered"), likely on the RADIUS server.
If I dow a local test with radtest I can see there something
radtest <PC MAC Address> none localhost 10 testing123
The firewall isn't blocking the RADIUS server talking to itself. -- Matthew
On Aug 11, 2021, at 5:50 AM, Dennis Schneck <dennis.schneck@schulergroup.com> wrote:
Hello, if the Switch sends requests can see only in wireshark this: ICMP 435 Destination unreachable (Communication administratively filtered)
$ tshark -Y "ip.addr==192.168.1.0/24" Capturing on 'eth0' 109 12.985452883 192.168.1.78 → 172.16.1.28 RADIUS 407 Access-Request id=5 110 12.985550915 172.16.1.28 → 192.168.1.78 ICMP 435 Destination unreachable (Communication administratively filtered)
If your RADIUS server is 172.16.1.28, then there's a firewall / SELinux / something which is generating that ICMP message. FreeRADIUS
but in debug mode (raduisd -X) can see nothing.
Because the Operating System is generating the ICMP messages, and is refusing to send RADIUS packets to FreeRADIUS.
What did I wrong ?
No amount of poking the FreeRADIUS configuration will fix this issue. The issue is in the local operating system. Most Linux distributions do not come with such ICMP filters enabled. So, it's likely something done to your local system. If not by you, by another administrator. Alan DeKok.
participants (4)
-
Alan DeKok -
Dennis Schneck -
Matthew Newton -
Sven Hartge