Re: [gentoo-user] Wireless DHCP takes over resolv.conf
The solution I use when dealing with the problem of network software overwriting '/etc/resolf.conf' is to make that file immutable with 'chattr +i'. Not quite an answer to your question on nameserver prioritization, but could be useful to prevent your nameservers from being changed. -- Marat On 07/09/2016 07:53 AM, Mick wrote: > Hi All, > > I just noticed my resolv.conf is topped up with the nameservers of the > wireless LAN I happen to be associated at the time and my wired ethernet > nameserver(s) are pushed further down. This happens despite the fact that I > have configured my wired ethernet to have a lesser priority than the wired > NIC. > > For example: > > less /etc/resolv.conf > # Generated by dhcpcd from wlan0.dhcp, enp11s0.dhcp > # /etc/resolv.conf.head can replace this line > domain openwifi > nameserver 192.168.22.22 > nameserver 192.168.22.23 > nameserver 10.10.10.254 > # /etc/resolv.conf.tail can replace this line > > The first 3 non-commented entries were produced by wlan0, demoting my wired > ethernet nameserver. > > ip route show > default via 10.10.10.254 dev enp11s0 metric 10 > default via 10.160.95.1 dev wlan0 metric 20 > 10.10.10.0/24 dev enp11s0 proto kernel scope link src 10.10.10.7 metric > 10 > 10.160.95.0/29 dev wlan0 proto kernel scope link src 10.160.95.2 metric > 20 > 127.0.0.0/8 dev lo scope host > > If I am associated, but not authenticated with the wireless LAN, any URLs I > try to visit will be queried with the 192.168.22.2* nameserver, before it > times out and 10.10.10.254 takes over. > > Waiting for URLs to resolve becomes tedious after a while. Is there a way to > prioritise nameservers so that the NIC metric is respected, whenever the > resolv.conf content is updated? >
Re: [gentoo-user] Wireless DHCP takes over resolv.conf
On 11 July 2016 at 17:31, Alan McKinnon wrote: > On 11/07/2016 10:32, Emanuele Rusconi wrote: > > Wouldn't it be better to just use the same servers for both wired and > > wireless? It's what I use and it works flawlessly. > > It works flawlessly *for you*, but by no means can you consider it > correct or stable. > > There is no guarantee that a wired and wireless network will use the > same dns caches. > > If it happens to work, great, use it. But be aware there will come a day > when that is no longer true. That's why I phrased my suggestion as a question. I'm honestly curious: aren't DNS servers like Google ones (8.8.8.8 etc.) supposed to be reachable from anywhere? If you can't reach them, isn't your connectivity inherently broken? I'm sure I'm missing something here. -- Emanuele Rusconi
Re: [gentoo-user] Wireless DHCP takes over resolv.conf
On 11/07/2016 20:13, Mick wrote: On Monday 11 Jul 2016 17:31:29 Alan McKinnon wrote: On 11/07/2016 10:32, Emanuele Rusconi wrote: Wouldn't it be better to just use the same servers for both wired and wireless? It's what I use and it works flawlessly. It works flawlessly *for you*, but by no means can you consider it correct or stable. There is no guarantee that a wired and wireless network will use the same dns caches. Yep, furthermore this is a laptop which is taken around the place and plugged in and out of wired and wireless networks. If it happens to work, great, use it. But be aware there will come a day when that is no longer true. When I get a minute I'll have a look at net-dns/openresolv which Fernando suggested. I think it will do what want. why don't you go with the dns server addresses supplied by each network's dhcp? Presumably the admin put them their because they work on that network.
Re: [gentoo-user] Wireless DHCP takes over resolv.conf
On Monday 11 Jul 2016 17:31:29 Alan McKinnon wrote: > On 11/07/2016 10:32, Emanuele Rusconi wrote: > > Wouldn't it be better to just use the same servers for both wired and > > wireless? It's what I use and it works flawlessly. > > It works flawlessly *for you*, but by no means can you consider it > correct or stable. > > There is no guarantee that a wired and wireless network will use the > same dns caches. Yep, furthermore this is a laptop which is taken around the place and plugged in and out of wired and wireless networks. > If it happens to work, great, use it. But be aware there will come a day > when that is no longer true. When I get a minute I'll have a look at net-dns/openresolv which Fernando suggested. I think it will do what want. -- Regards, Mick signature.asc Description: This is a digitally signed message part.
Re: [gentoo-user] Wireless DHCP takes over resolv.conf
On 11/07/2016 10:32, Emanuele Rusconi wrote: > Wouldn't it be better to just use the same servers for both wired and > wireless? It's what I use and it works flawlessly. It works flawlessly *for you*, but by no means can you consider it correct or stable. There is no guarantee that a wired and wireless network will use the same dns caches. If it happens to work, great, use it. But be aware there will come a day when that is no longer true. -- Alan McKinnon alan.mckin...@gmail.com
Re: [gentoo-user] Wireless DHCP takes over resolv.conf
Wouldn't it be better to just use the same servers for both wired and wireless? It's what I use and it works flawlessly. In that case you have at least a couple of options: The second line says: # /etc/resolv.conf.head can replace this line So, you can just put your preferred servers in the /etc/resolv.conf.head file and they will be written at the top of /etc/resolv.conf . Or, you can write your own /etc/resolv.conf and add this line to your /etc/dhcpcd.conf : nohook resolv.conf This is the same as the -C option, and tells dhcpcd to not overwrite /etc/resolv.conf . -- Emanuele Rusconi
Re: [gentoo-user] Wireless DHCP takes over resolv.conf
-BEGIN PGP SIGNED MESSAGE- Hash: SHA256 On 07/09/2016 03:25 PM, Mick wrote: > On Saturday 09 Jul 2016 11:34:59 Fernando Rodriguez wrote: >> On 07/09/2016 10:53 AM, Mick wrote: >>> Hi All, >>> >>> I just noticed my resolv.conf is topped up with the nameservers of the >>> wireless LAN I happen to be associated at the time and my wired ethernet >>> nameserver(s) are pushed further down. This happens despite the fact that >>> I have configured my wired ethernet to have a lesser priority than the >>> wired NIC. >>> >>> For example: >>> >>> less /etc/resolv.conf >>> # Generated by dhcpcd from wlan0.dhcp, enp11s0.dhcp >>> # /etc/resolv.conf.head can replace this lineL >>> domain openwifi >>> nameserver 192.168.22.22 >>> nameserver 192.168.22.23 >>> nameserver 10.10.10.254 >>> # /etc/resolv.conf.tail can replace this line >>> >>> The first 3 non-commented entries were produced by wlan0, demoting my >>> wired >>> ethernet nameserver. >>> >>> ip route show >>> default via 10.10.10.254 dev enp11s0 metric 10 >>> default via 10.160.95.1 dev wlan0 metric 20 >>> 10.10.10.0/24 dev enp11s0 proto kernel scope link src 10.10.10.7 >>> metric 10 10.160.95.0/29 dev wlan0 proto kernel scope link src >>> 10.160.95.2 metric 20 127.0.0.0/8 dev lo scope host >>> >>> If I am associated, but not authenticated with the wireless LAN, any URLs >>> I >>> try to visit will be queried with the 192.168.22.2* nameserver, before it >>> times out and 10.10.10.254 takes over. >>> >>> Waiting for URLs to resolve becomes tedious after a while. Is there a way >>> to prioritise nameservers so that the NIC metric is respected, whenever >>> the resolv.conf content is updated? >> >> Look at the -C option on dhcpcd's man page. It is done by a dhcpcd hook that >> you can disable with that option. Where to specify it depends on what >> you're using to manage your network connections. > > Thanks, that'll work, but it is a nuclear option because, as I understand it, > it will work all the time. So when the ethernet cable is disconnected the > wireless will not be able to obtain nameservers. Check out net-dns/openresolv [1]. I've never used it but it's mean to solve that problem. If you use NetworkManager I think all you need to do is enable that use flag. [1] http://roy.marples.name/projects/openresolv/index -BEGIN PGP SIGNATURE- Version: GnuPG v2 iQIcBAEBCAAGBQJXgVYtAAoJEPbOFX/5Ulwc0MIP/RcyQ6dAed9YAC9KOMwCrfmu SsONlWAaBgCSrHKGZcI3a4G9WKd8kyGPUM2deSP02JBNTDiHwZxwb494dQk2u2HN Y6WoHE65F7LE6er5HaPBW28qTSHQ0BaH2SNQzJsId+hl0CnVfFr8t6IU+Qav7W2m Oyeh3Wph5kDHx2cX80Czs45lWkxIbcsx2bN8a4G9ZjSk23KDtkvG5F5CgZgU/aYK F0815O0lqzA+CLhSgzQsYOeF5aRBQ1jEh+EHSWC6Py6AuSNHmw5YanrnpelzFNHD GhG26b2aKuXcUI7DW2MtF3vnMqcQ8nXIZjpkoKF0JAy31ruPvKJVCWMuVUrZD/l1 uTqo1DhfUyaynjG2cX5TZ9+pk8GfAaRG+W9bq/xu/v4zAKxfVZS8DUo2VOMvZqdv YO8azzbwqyPfG7M6mF6NPLBR4h+EQYpCHoh8B8u+gsXkRxsDB5zlKqaXGO579p15 tvaAxbpW6veDH8taQITEnG7cGLm+cv9raVYmBK2rcOvPSnbfYE/A+UifmQ9gBNp7 CzEpEryIuUIL+ztkgQpLxZY1ldAt3WuiB99i+rcksVvsOO3mSHq10298M+PcfM0g tvCkL6ttDhPiTQCXvzHuaH8lvxfHdN70LUrKngnC2NtQpzXdgFcSJynJ26wx6xrU P6Txb5Q7nzPO+bdF7otO =2Z4B -END PGP SIGNATURE-
Re: [gentoo-user] Wireless DHCP takes over resolv.conf
On Saturday 09 Jul 2016 11:34:59 Fernando Rodriguez wrote: > On 07/09/2016 10:53 AM, Mick wrote: > > Hi All, > > > > I just noticed my resolv.conf is topped up with the nameservers of the > > wireless LAN I happen to be associated at the time and my wired ethernet > > nameserver(s) are pushed further down. This happens despite the fact that > > I have configured my wired ethernet to have a lesser priority than the > > wired NIC. > > > > For example: > > > > less /etc/resolv.conf > > # Generated by dhcpcd from wlan0.dhcp, enp11s0.dhcp > > # /etc/resolv.conf.head can replace this lineL > > domain openwifi > > nameserver 192.168.22.22 > > nameserver 192.168.22.23 > > nameserver 10.10.10.254 > > # /etc/resolv.conf.tail can replace this line > > > > The first 3 non-commented entries were produced by wlan0, demoting my > > wired > > ethernet nameserver. > > > > ip route show > > default via 10.10.10.254 dev enp11s0 metric 10 > > default via 10.160.95.1 dev wlan0 metric 20 > > 10.10.10.0/24 dev enp11s0 proto kernel scope link src 10.10.10.7 > > metric 10 10.160.95.0/29 dev wlan0 proto kernel scope link src > > 10.160.95.2 metric 20 127.0.0.0/8 dev lo scope host > > > > If I am associated, but not authenticated with the wireless LAN, any URLs > > I > > try to visit will be queried with the 192.168.22.2* nameserver, before it > > times out and 10.10.10.254 takes over. > > > > Waiting for URLs to resolve becomes tedious after a while. Is there a way > > to prioritise nameservers so that the NIC metric is respected, whenever > > the resolv.conf content is updated? > > Look at the -C option on dhcpcd's man page. It is done by a dhcpcd hook that > you can disable with that option. Where to specify it depends on what > you're using to manage your network connections. Thanks, that'll work, but it is a nuclear option because, as I understand it, it will work all the time. So when the ethernet cable is disconnected the wireless will not be able to obtain nameservers. -- Regards, Mick signature.asc Description: This is a digitally signed message part.
Re: [gentoo-user] Wireless DHCP takes over resolv.conf
-BEGIN PGP SIGNED MESSAGE- Hash: SHA256 On 07/09/2016 10:53 AM, Mick wrote: > Hi All, > > I just noticed my resolv.conf is topped up with the nameservers of the > wireless LAN I happen to be associated at the time and my wired ethernet > nameserver(s) are pushed further down. This happens despite the fact that I > have configured my wired ethernet to have a lesser priority than the wired > NIC. > > For example: > > less /etc/resolv.conf > # Generated by dhcpcd from wlan0.dhcp, enp11s0.dhcp > # /etc/resolv.conf.head can replace this lineL > domain openwifi > nameserver 192.168.22.22 > nameserver 192.168.22.23 > nameserver 10.10.10.254 > # /etc/resolv.conf.tail can replace this line > > The first 3 non-commented entries were produced by wlan0, demoting my wired > ethernet nameserver. > > ip route show > default via 10.10.10.254 dev enp11s0 metric 10 > default via 10.160.95.1 dev wlan0 metric 20 > 10.10.10.0/24 dev enp11s0 proto kernel scope link src 10.10.10.7 metric > 10 > 10.160.95.0/29 dev wlan0 proto kernel scope link src 10.160.95.2 metric > 20 > 127.0.0.0/8 dev lo scope host > > If I am associated, but not authenticated with the wireless LAN, any URLs I > try to visit will be queried with the 192.168.22.2* nameserver, before it > times out and 10.10.10.254 takes over. > > Waiting for URLs to resolve becomes tedious after a while. Is there a way to > prioritise nameservers so that the NIC metric is respected, whenever the > resolv.conf content is updated? > Look at the -C option on dhcpcd's man page. It is done by a dhcpcd hook that you can disable with that option. Where to specify it depends on what you're using to manage your network connections. -BEGIN PGP SIGNATURE- Version: GnuPG v2 iQIcBAEBCAAGBQJXgRmiAAoJEPbOFX/5UlwckloP/RS5QM9FrJN/EGk5F2v3vakC DP5EIqx103d2Qte91zmBPNGpq3PKCDi2aQza3dIspQ6zfR/I4P8u3ODbsclIc1U9 gikAKos+fVB+6nVCAVKKrpyWsDGJ7Qgupu+x1SOP1MDLNBkDnIgS2n72S0Z6FCUF d5q4lUyp5w8G/+A+m01FnpFZCcBZBfBLQY9cccUR6CkkuJW1+vjPzppJoeQ032CT FRqebV17htnJzuME85KcVTuawiO8xuHM/Y9tkVupe8fyEPlG8k53WY4XNh3KuuEZ gIqjsYJWEJeH0HQp9MFM+HBesJrRAgaTT0jAmEXiNcKeVx0UHZppNfSl8q/NKT+o rChcHJ62lrW8Q4gHtf7I5tkXyZdfLM1TdiViLTKUR9EGkV+lnoQFHDbe0+MCirkC /2XsbYTUBWb5zMwCH0I9QCjA8LsCD5I4YK+strXld+6+yaGRDNh2XUo36uJCoJNZ 6fbOweDHCV9CMgkHH78swYZa3Fu7z8n4my7i/lEo9L+7r0IIcspDrxhgtP4T7qLu UYrWoOTALUwiyqtIry7FnciifdlrCoURm9rAp9jZAz8PTha33d2Vhlj/tKiL8v3x YmuB+Tz9/yLp8VXpR5h2hO4i2WTOQnW+vgugw0v3DJqE3JRKqqGsfhX9gA4JTDz2 Jwp9Faoag1hKEf8Dl8I9 =TqPa -END PGP SIGNATURE-
[gentoo-user] Wireless DHCP takes over resolv.conf
Hi All, I just noticed my resolv.conf is topped up with the nameservers of the wireless LAN I happen to be associated at the time and my wired ethernet nameserver(s) are pushed further down. This happens despite the fact that I have configured my wired ethernet to have a lesser priority than the wired NIC. For example: less /etc/resolv.conf # Generated by dhcpcd from wlan0.dhcp, enp11s0.dhcp # /etc/resolv.conf.head can replace this line domain openwifi nameserver 192.168.22.22 nameserver 192.168.22.23 nameserver 10.10.10.254 # /etc/resolv.conf.tail can replace this line The first 3 non-commented entries were produced by wlan0, demoting my wired ethernet nameserver. ip route show default via 10.10.10.254 dev enp11s0 metric 10 default via 10.160.95.1 dev wlan0 metric 20 10.10.10.0/24 dev enp11s0 proto kernel scope link src 10.10.10.7 metric 10 10.160.95.0/29 dev wlan0 proto kernel scope link src 10.160.95.2 metric 20 127.0.0.0/8 dev lo scope host If I am associated, but not authenticated with the wireless LAN, any URLs I try to visit will be queried with the 192.168.22.2* nameserver, before it times out and 10.10.10.254 takes over. Waiting for URLs to resolve becomes tedious after a while. Is there a way to prioritise nameservers so that the NIC metric is respected, whenever the resolv.conf content is updated? -- Regards, Mick signature.asc Description: This is a digitally signed message part.
