Did anybody else experience an incident where RouterOS, running on RB751U-2HnD, fails to respond to DNS queries and needs to be rebooted as in:
dig http://www.google.com @1.2.3.4
; <<>> DiG 9.3.4-P1 <<>> http://www.google.com @1.2.3.4
; (1 server found)
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 4216
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;www.google.com. IN A
;; Query time: 130 msec
[ ...]
[ reboot]
dig http://www.google.com @1.2.3.4
; <<>> DiG 9.3.4-P1 <<>> http://www.google.com @1.2.3.4
; (1 server found)
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 13443
;; flags: qr rd ra; QUERY: 1, ANSWER: 7, AUTHORITY: 4, ADDITIONAL: 4
;; QUESTION SECTION:
;www.google.com. IN A
;; ANSWER SECTION:
http://www.google.com. 549765 IN CNAME http://www.l.google.com.
http://www.l.google.com. 170 IN A 74.125.65.147
http://www.l.google.com. 170 IN A 74.125.65.99
http://www.l.google.com. 170 IN A 74.125.65.103
http://www.l.google.com. 170 IN A 74.125.65.104
http://www.l.google.com. 170 IN A 74.125.65.105
http://www.l.google.com. 170 IN A 74.125.65.106
[ ... ]
I only had about 300 entries in the cache at the time.