Some Linux Disros interference the network

Hello. I have a Network with Router Os and Hotspot is running on it. It’s working as intended and there is no problem except when a Linux client is connected to the network (not login to the network; just connect to one of the access points) and then the other users can’t login to the hotspot and even ping the Router IP; it seems that some services on Linux cause Network request routed to Linux node instead of Router. anyone can help with this strange problem? any help be appreciated.

Can you give some more info? The config? The IP of the linux host when you got the issue? A packet capture?

Common cause for these problems is that client’s device has DHCP server enabled that broadcasts false data to the network. Different kind of “sharing” or “server” functionalities. MikroTik has functionality to notice rogue DHCP servers and send you notification.

Thanks for your answer. I’ve checked the present of rogue DHCP server and there was nothing, even activate Mikrotik rouge DHCP server alert and nothing find . do you have any other idea that what is root cause of this problem.

Thanks for your answer. this a Wireshark sniff for packets that are sent to network by Linux node if can help

No.	Time	Source	Destination	Protocol	Length	Info	src Mac
1063	52.946910	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
1068	53.069168	172.17.254.162	224.0.0.251	MDNS	225	Standard query 0x0000 ANY ???'s remote desktop on ???-desktop._rfb._tcp.local, "QM" question ANY ???-desktop.local, "QM" question ANY 162.254.17.172.in-addr.arpa, "QM" question A 172.17.254.162 PTR ???-desktop.local SRV 0 0 5900 ???-desktop.local TXT	Tp-LinkT_bd:22:87
1069	53.107940	172.17.254.162	224.0.0.251	MDNS	156	Standard query response 0x0000 PTR _rfb._tcp.local PTR ???'s remote desktop on ???-desktop._rfb._tcp.local	Tp-LinkT_bd:22:87
1071	53.318731	172.17.254.162	224.0.0.251	MDNS	225	Standard query 0x0000 ANY ???'s remote desktop on ???-desktop._rfb._tcp.local, "QM" question ANY ???-desktop.local, "QM" question ANY 162.254.17.172.in-addr.arpa, "QM" question A 172.17.254.162 PTR ???-desktop.local SRV 0 0 5900 ???-desktop.local TXT	Tp-LinkT_bd:22:87
1082	53.569914	172.17.254.162	224.0.0.251	MDNS	225	Standard query 0x0000 ANY ???'s remote desktop on ???-desktop._rfb._tcp.local, "QM" question ANY ???-desktop.local, "QM" question ANY 162.254.17.172.in-addr.arpa, "QM" question A 172.17.254.162 PTR ???-desktop.local SRV 0 0 5900 ???-desktop.local TXT	Tp-LinkT_bd:22:87
1087	53.770040	172.17.254.162	224.0.0.251	MDNS	207	Standard query response 0x0000 TXT, cache flush A, cache flush 172.17.254.162 PTR, cache flush ???-desktop.local SRV, cache flush 0 0 5900 ???-desktop.local	Tp-LinkT_bd:22:87
1089	53.945556	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
1090	54.282674	172.17.254.162	224.0.0.251	MDNS	217	Standard query response 0x0000 PTR _rfb._tcp.local PTR ???'s remote desktop on ???-desktop._rfb._tcp.local TXT, cache flush SRV, cache flush 0 0 5900 ???-desktop.local A, cache flush 172.17.254.162	Tp-LinkT_bd:22:87
1112	54.942219	172.17.254.162	224.0.0.251	MDNS	207	Standard query response 0x0000 TXT, cache flush A, cache flush 172.17.254.162 PTR, cache flush ???-desktop.local SRV, cache flush 0 0 5900 ???-desktop.local	Tp-LinkT_bd:22:87
1118	55.048739	172.17.254.162	224.0.0.251	MDNS	197	Standard query 0x0000 ANY d.2.4.8.e.c.6.8.6.0.8.0.c.7.e.9.0.0.0.0.0.0.0.0.0.0.0.0.0.8.e.f.ip6.arpa, "QM" question ANY ???-desktop.local, "QM" question AAAA fe80::9e7c:806:86ce:842d PTR ???-desktop.local	Tp-LinkT_bd:22:87
1123	55.299073	172.17.254.162	224.0.0.251	MDNS	197	Standard query 0x0000 ANY d.2.4.8.e.c.6.8.6.0.8.0.c.7.e.9.0.0.0.0.0.0.0.0.0.0.0.0.0.8.e.f.ip6.arpa, "QM" question ANY ???-desktop.local, "QM" question AAAA fe80::9e7c:806:86ce:842d PTR ???-desktop.local	Tp-LinkT_bd:22:87
1129	55.549682	172.17.254.162	224.0.0.251	MDNS	197	Standard query 0x0000 ANY d.2.4.8.e.c.6.8.6.0.8.0.c.7.e.9.0.0.0.0.0.0.0.0.0.0.0.0.0.8.e.f.ip6.arpa, "QM" question ANY ???-desktop.local, "QM" question AAAA fe80::9e7c:806:86ce:842d PTR ???-desktop.local	Tp-LinkT_bd:22:87
1130	55.550809	172.17.254.162	224.0.0.251	MDNS	87	Standard query response 0x0000 A, cache flush 172.17.254.162	Tp-LinkT_bd:22:87
1138	55.750672	172.17.254.162	224.0.0.251	MDNS	185	Standard query response 0x0000 PTR, cache flush ???-desktop.local AAAA, cache flush fe80::9e7c:806:86ce:842d	Tp-LinkT_bd:22:87
1143	55.949255	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
1155	56.456136	172.17.254.162	224.0.0.251	MDNS	245	Standard query response 0x0000 PTR _rfb._tcp.local PTR ???'s remote desktop on ???-desktop._rfb._tcp.local TXT, cache flush SRV, cache flush 0 0 5900 ???-desktop.local AAAA, cache flush fe80::9e7c:806:86ce:842d A, cache flush 172.17.254.162	Tp-LinkT_bd:22:87
1174	56.923318	172.17.254.162	224.0.0.251	MDNS	157	Standard query response 0x0000 PTR, cache flush ???-desktop.local	Tp-LinkT_bd:22:87
1181	57.115781	172.17.254.162	224.0.0.251	MDNS	235	Standard query response 0x0000 TXT, cache flush A, cache flush 172.17.254.162 PTR, cache flush ???-desktop.local SRV, cache flush 0 0 5900 ???-desktop.local AAAA, cache flush fe80::9e7c:806:86ce:842d	Tp-LinkT_bd:22:87
1231	59.096770	172.17.254.162	224.0.0.251	MDNS	185	Standard query response 0x0000 PTR, cache flush ???-desktop.local AAAA, cache flush fe80::9e7c:806:86ce:842d	Tp-LinkT_bd:22:87
1254	59.946642	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
1393	67.949839	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
1709	83.956195	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
2357	115.958239	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
3635	179.958283	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
4747	233.215003	172.17.254.162	224.0.0.251	MDNS	79	Standard query 0x0000 PTR _scanner._tcp.local, "QM" question	Tp-LinkT_bd:22:87
4764	234.001780	172.17.254.162	224.0.0.251	MDNS	79	Standard query 0x0000 PTR _scanner._tcp.local, "QM" question	Tp-LinkT_bd:22:87
4781	234.883965	172.17.254.162	255.255.255.255	UDP	60	47994 → 3289 Len=15	Tp-LinkT_bd:22:87
4797	235.894850	172.17.254.162	255.255.255.255	UDP	79	36018 → 1124 Len=37	Tp-LinkT_bd:22:87
6304	307.958194	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
16450	563.956379	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
17171	588.318005	172.17.254.162	255.255.255.255	DHCP	342	DHCP Request  - Transaction ID 0xd6c94d59	Tp-LinkT_bd:22:87
27909	1075.953349	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
28765	1116.259549	172.17.254.162	255.255.255.255	DHCP	342	DHCP Request  - Transaction ID 0xd6c94d59	Tp-LinkT_bd:22:87
47036	1651.339738	172.17.254.162	255.255.255.255	DHCP	342	DHCP Request  - Transaction ID 0xd6c94d59	Tp-LinkT_bd:22:87
73152	2099.947330	172.17.254.162	224.0.0.251	MDNS	160	Standard query 0x0000 PTR _nfs._tcp.local, "QM" question PTR _ftp._tcp.local, "QM" question PTR _webdav._tcp.local, "QM" question PTR _webdavs._tcp.local, "QM" question PTR _sftp-ssh._tcp.local, "QM" question PTR _smb._tcp.local, "QM" question PTR _afpovertcp._tcp.local, "QM" question	Tp-LinkT_bd:22:87
75145	2181.027522	172.17.254.162	255.255.255.255	DHCP	342	DHCP Request  - Transaction ID 0xd6c94d59	Tp-LinkT_bd:22:87
98553	2708.529788	172.17.254.162	255.255.255.255	DHCP	342	DHCP Request  - Transaction ID 0xd6c94d59	Tp-LinkT_bd:22:87
98961	2718.504579	172.17.254.162	255.255.255.255	DHCP	342	DHCP Request  - Transaction ID 0xd6c94d59	Tp-LinkT_bd:22:87

Device with IP address 172.17.254.162 is trying to perform some service auto-discovery … and destination for most is a multicast address, except for DHCP where destination is a global broadcast address. It could be that it’s also advertising its own services … using MDNS / bonjour protocol.

Last column (src MAC) says that offending device is some TpLink device.

Any other suggestions for this problem?