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resolv.conf - how to reload?

I have slackware machines setup with static ips and I had to change the resolv.conf file.

Does the machine have to be rebooted?

What command can I run to reload the resolv.conf file without rebooting?

thx

coldbeer --

In my experience, editing resolv.conf has always seemed to be 'good enough' ...

YMMV ... ( and I am not sure what applications may be caching DNS )

-- kjh

This is my resolv.conf:

Code:

# cat /etc/resolv.conf



domain kjh.home

search kjh.home

nameserver 127.0.0.1

nameserver 8.8.8.8

nameserver 192.168.0.1

What server is resolving hostnames for me ( note the SERVER section at the end of the dig output ) ?

Code:

; <<>> DiG 9.10.5-P3 <<>> any google.com

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6319

;; flags: qr rd ra; QUERY: 1, ANSWER: 13, AUTHORITY: 4, ADDITIONAL: 5



;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; udp: 4096

;; QUESTION SECTION:

;google.com.                    IN      ANY



;; ANSWER SECTION:

google.com.            86281  IN      CAA    0 issue "pki.goog"



<<snip>>



;; Query time: 0 msec

;; SERVER: 127.0.0.1#53(127.0.0.1)

;; WHEN: Tue Jan 09 09:21:20 CST 2018

;; MSG SIZE  rcvd: 458

Change my resolv.conf

Code:

# cat /etc/resolv.conf



domain kjh.home

search kjh.home

nameserver 8.8.8.8

nameserver 192.168.0.1

nameserver 127.0.0.1

Which SERVER is resolving host names now ?

Code:

# dig any google.com



<<snip>> - jump to the punch line ...



;; Query time: 36 msec

;; SERVER: 8.8.8.8#53(8.8.8.8)

;; WHEN: Tue Jan 09 09:23:54 CST 2018

;; MSG SIZE  rcvd: 384

Looks like resolv.conf changes are effective immediately.

Using the 'dig' command the dns host used is shown at the bottom:

;; Query time: 81 msec
;; SERVER: 144.111.55.235#53(144.111.55.235)
;; WHEN: Tue Jan 09 10:21:30 EST 2018

After I change the resolv.conf and run dig again:

;; Query time: 0 msec
;; SERVER: 144.111.44.79#53(144.111.44.79)
;; WHEN: Tue Jan 09 10:22:11 EST 2018
;; MSG SIZE rcvd: 268

Quote:

Originally Posted by kjhambrick (Post 5804170)

coldbeer --

In my experience, editing resolv.conf has always seemed to be 'good enough' ...

YMMV ... ( and I am not sure what applications may be caching DNS )

-- kjh

This is my resolv.conf:

Code:

# cat /etc/resolv.conf



domain kjh.home

search kjh.home

nameserver 127.0.0.1

nameserver 8.8.8.8

nameserver 192.168.0.1

What server is resolving hostnames for me ( note the SERVER section at the end of the dig output ) ?

Code:

; <<>> DiG 9.10.5-P3 <<>> any google.com

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6319

;; flags: qr rd ra; QUERY: 1, ANSWER: 13, AUTHORITY: 4, ADDITIONAL: 5



;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; udp: 4096

;; QUESTION SECTION:

;google.com.                    IN      ANY



;; ANSWER SECTION:

google.com.            86281  IN      CAA    0 issue "pki.goog"



<<snip>>



;; Query time: 0 msec

;; SERVER: 127.0.0.1#53(127.0.0.1)

;; WHEN: Tue Jan 09 09:21:20 CST 2018

;; MSG SIZE  rcvd: 458

Change my resolv.conf

Code:

# cat /etc/resolv.conf



domain kjh.home

search kjh.home

nameserver 8.8.8.8

nameserver 192.168.0.1

nameserver 127.0.0.1

Which SERVER is resolving host names now ?

Code:

# dig any google.com



<<snip>> - jump to the punch line ...



;; Query time: 36 msec

;; SERVER: 8.8.8.8#53(8.8.8.8)

;; WHEN: Tue Jan 09 09:23:54 CST 2018

;; MSG SIZE  rcvd: 384

I just did the same thing :-) Thanks!

Changes to resolv.conf do eventually come into effect, but can take a couple of minutes to "stick," IME. I wonder if there's a way of "forcing" the issue.

By the way, NetworkManager, if you are using it, will overwrite changes to resolv.conf.

Quote:

Originally Posted by Fat_Elvis (Post 5806203)

By the way, NetworkManager, if you are using it, will overwrite changes to resolv.conf.

Which can be prevented if the file system allows it with:

Code:

chattr -V +i /etc/resolv.conf

I do that because my web hoster's name servers are sometimes slow so I prefer to use public ones.

Quote:

Originally Posted by Didier Spaier (Post 5806215)

Which can be prevented if the file system allows it with:

Code:

chattr -V +i /etc/resolv.conf

I do that because my web hoster's name servers are sometimes slow so I prefer to use public ones.

Good info, thanks! I should get around to learning how to set up wi-fi manually one of these days.