Unlike I stated earlier today…
It’s not DNS
There’s no way it’s DNS
It was DNS
… this time it was not DNS. But let’s start from the beginning.
two lonely OpenSUSE virtual machines
I inherited two OpenSUSE VMs from a departing colleague.
After changing passwords and cataloging what services are installed, I tried to update the VMs… and got the following errors…
# zypper refresh
Problem retrieving files from 'Haupt-Repository (NON-OSS)'.
Download (curl) error for 'http://download.opensuse.org/tumbleweed/repo/non-oss/repodata/repomd.xml':
Error code: Connection failed
Error message:
Please see the above error message for a hint.
Skipping repository 'Haupt-Repository (NON-OSS)' because of the above error.
At first I thought that maybe the repository URLs are out of date, but they are ok, and I can access them in the browser.
some network problems ahead
Ok, let’s ping a host…
# ping www.google.de
ping: connect: Network is unreachable
Let’s have a look whether a DNS server is configured…
cat /etc/resolv.conf
### Call "netconfig update -f" to force adjusting of /etc/resolv.conf.
nameserver 192.168.1.220
Looks good.
Let’s see whether the DNS server can be pinged…
# ping 192.168.1.220
PING 192.168.1.220 (192.168.1.220) 56(84) bytes of data.
64 bytes from 192.168.1.220: icmp_seq=1 ttl=64 time=0.251 ms
64 bytes from 192.168.1.220: icmp_seq=2 ttl=64 time=0.247 ms
...
Okay, looks good.
Let’s dig google…
# dig www.google.de
; <<>> DiG 9.16.6 <<>> www.google.de
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 31174
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; COOKIE: 5d52301444dda5910100000060e45814feffe9a478a3b819 (good)
;; QUESTION SECTION:
;www.google.de. IN A
;; ANSWER SECTION:
www.google.de. 296 IN A 142.250.74.195
;; Query time: 4 msec
;; SERVER: 192.168.1.220#53(192.168.1.220)
;; WHEN: Tue Jul 06 15:18:12 CEST 2021
;; MSG SIZE rcvd: 86
Hm, this also works…
Maybe the network is misconfigured?
2: ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:50:56:9c:74:bd brd ff:ff:ff:ff:ff:ff
altname enp11s0
inet 192.168.1.27/24 brd 192.168.1.255 scope global ens192
valid_lft forever preferred_lft forever
inet6 fe80::250:56ff:fe9c:74bd/64 scope link
valid_lft forever preferred_lft forever
Looks okay, too.
Narrator: The author starts scratching his head.
the missing piece
I got the crucial hint from Chaotenchaos, in the most minimal way of communication :-)
route -n
gaia:~ # route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0
172.18.0.0 0.0.0.0 255.255.0.0 U 0 0 0 br-aac7f7b32b3d
172.19.0.0 0.0.0.0 255.255.0.0 U 0 0 0 br-22d0066bc0ac
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 ens192
Oh yeah, there is something missing… the default route!!
Let’s add a new default gateway …
route add default gw 192.168.1.1 ens192
ping google.de immediately worked.
permanent solution
As you may know, route add ... is not a permanent change.
After a reboot or a sudo service network restart the changes are lost.
For OpenSUSE you need to add the configuration in /etc/sysconfig/network/routes,
in the form of…
# Destination Gateway Netmask Interface
e.g.
default 192.168.1.1 - ens192
Mission completed!
almost
The second OpenSUSE VM had no route command installed.
Ok, let’s install it quickly… except I can’t install anything as I cannot access the Internet :-/
Ok, let’s add a temporary route …
# route add default gw 192.168.1.1 ens192
… except there is no route command available :-o
route and a couple of other network commands are deprecated,
and most of them are replaced by the mighty ip command.
Instead of route add... I used …
# ip route add default via 192.168.1.1
Also, instead of route -n to show all available routes,
you can use ip route.
Interestingly, there was no /etc/sysconfig/network/routes file.
Creating it and adding the default gateway worked, though.
Mission completed … this time for real!