(network unreachable) error in my server logs
I’m getting lots of network unreachable lines in my Centos’ messages log file. They seem they can’t resolve to certain addresses which I do not have any ideas why my server has to resolve to them in the first place. Could anyone let me know the origin of such error? Am I under an attack?
Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving './DNSKEY/IN': 2001:503:ba3e::2:30#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving './NS/IN': 2001:503:ba3e::2:30#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'dlv.isc.org/DNSKEY/IN': 2001:500:48::1#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'dlv.isc.org/DNSKEY/IN': 2001:4f8:0:2::19#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns.isc.afilias-nst.info/A/IN': 2001:500:2f::f#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns.isc.afilias-nst.info/AAAA/IN': 2001:500:2f::f#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns.isc.afilias-nst.info/A/IN': 2001:500:1::803f:235#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns.isc.afilias-nst.info/AAAA/IN': 2001:500:1::803f:235#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns.isc.afilias-nst.info/A/IN': 2001:503:c27::2:30#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns.isc.afilias-nst.info/AAAA/IN': 2001:503:c27::2:30#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns.isc.afilias-nst.info/A/IN': 2001:500:1a::1#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'dlv.isc.org/DNSKEY/IN': 2001:4f8:0:2::20#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'dlv.isc.org/DNSKEY/IN': 2001:500:60::29#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns1.isc.ultradns.net/A/IN': 2001:7fd::1#53 Oct 23 11:39:03 server named[1585]: error (network unreachable) resolving 'ns1.isc.ultradns.net/AAAA/IN': 2001:7fd::1#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'ns2.isc.ultradns.net/A/IN': 2610:a1:1014::e8#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.org/A/IN': 2001:500:e::1#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.org/AAAA/IN': 2001:500:e::1#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.org/A/IN': 2001:500:40::1#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.org/AAAA/IN': 2001:500:40::1#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.org/AAAA/IN': 2001:502:4612::e8#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.info/AAAA/IN': 2610:a1:1016::e8#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.info/A/IN': 2610:a1:1016::e8#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.co.uk/AAAA/IN': 2610:a1:1017::e8#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.biz/A/IN': 2610:a1:1015::e8#53 Oct 23 11:39:04 server named[1585]: error (network unreachable) resolving 'pdns196.ultradns.com/AAAA/IN': 2001:502:f3ff::e8#53 Oct 23 11:39:04 server named[1585]: client 93.113.174.225#46368: query (cache) 'adobe.com/A/IN' denied Oct 23 11:39:04 server named[1585]: client 93.113.174.225#23736: query (cache) 'adobe.com/A/IN' denied Oct 23 11:39:04 server lfd[1196]: SYSLOG check [Lga6AZUNsgZGaVQX] options < //listen-on port 53 < 127.0.0.1; >; //listen-on-v6 port 53 < ::1; >; directory "/var/named"; dump-file "/var/named/data/cache_dump.db"; statistics-file "/var/named/data/named_stats.txt"; memstatistics-file "/var/named/data/named_mem_stats.txt"; //allow-query < localhost; >; allow-recursion < localnets; >; dnssec-enable yes; dnssec-validation yes; dnssec-lookaside auto; /* Path to ISC DLV key */ bindkeys-file "/etc/named.iscdlv.key"; managed-keys-directory "/var/named/dynamic"; >; Virtual Machine Ubuntu 20.04 LTS : connect: Network is unreachable
I am new to linux and networking and today I have a «connect: Network is unreachable» when executing ping or sudo apt commands. I have seen some similar questions but still don’t have a clue about how to fix it. My ubuntu system is installled on my machine by VMware. messages I got after running sudo lshw -C network
*-network DISABLED description: Ethernet interface product: 82545EM Gigabit Ethernet Controller (Copper) vendor: Intel Corporation physical id: 1 bus info: pci@0000:02:01.0 logical name: ens33 version: 01 serial: 00:0c:29:c3:23:09 size: 1Gbit/s capacity: 1Gbit/s width: 64 bits clock: 66MHz capabilities: pm pcix bus_master cap_list rom ethernet physical logical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=e1000 driverversion=7.3.21-k8-NAPI duplex=full latency=0 link=no mingnt=255 multicast=yes port=twisted pair speed=1Gbit/s resources: irq:19 memory:fd5c0000-fd5dffff memory:fdff0000-fdffffff ioport:2000(size=64) memory:fd500000-fd50ffff # Let NetworkManager manage all devices on this system network: version: 2 renderer: NetworkManager 1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: ens33: mtu 1500 qdisc fq_codel state DOWN group default qlen 1000 link/ether 00:0c:29:c3:23:09 brd ff:ff:ff:ff:ff:ff «Network is unreachable» when attempting to ping google, but internal addresses work
I can get to other PCs in my house on the 192 network, but trying to go outside gives me the «network is unreachable» message. p3p1 is up with a good IP Address. Running Fedora 16. What should I do next to troubleshoot? All other PCs in the house are working (Windows, Mac).
Does any other PCs in your house have external internet access? (Can other PC ping google?) Restarted your house ADSL/cable/? modem?
Ping 8.8.4.4 fails @MariusMatutiae — same error, «connect: Network is unreachable.» But then I did a «route -n» and realized I had no gateway, added one («route add -net 0.0.0.0 gw 192.168.1.1 p3p1») and now I can ping 8.8.4.4 but still not 74.125.229.194 (google).
Yes @r3mus I can ping 192.168.1.1. On a working machine I go to «whatismyipaddress.com» and get my external address, and can ping that successfully as well from my failing machine.
3 Answers 3
You say all other pcs in your house have a connection. Then the problem lies only with your linux machine. There are several possibilities:
- You do have a connection, but you cannot reach your DNS; you can diagnose this by
if you can reach Google, then you have a connection, and you only need to update your DNS servers. Edit (as sudo) your /etc/resolv.conf file and add these two lines:
nameserver 8.8.8.8 nameserver 8.8.4.4 default via 192.168.11.1 dev wlan0 proto dhcp metric 600 (this is for my laptop). What is important is that the correct IP address of your router is shown exactly where mine (192.168.11.1) is shown. If an incorrect IP address is shown, or, worse, if the ip route show default command receives no reply, then your routing table has been corrupted. You may simply restore it by means of:
sudo ip route del default (only if the wrong IP address appears) sudo ip route add default via IP.address.OfYour.Router Error 101: Network is unreachable when trying to update
My ubuntu browsing this normally can not access any site, more apt-get update and even upgrade this giving error as shown below, what could it be?
sudo apt-get update Get:1 http://security.ubuntu.com/ubuntu xenial-security InRelease [94,5 kB] Hit:2 http://ppa.launchpad.net/webupd8team/sublime-text-3/ubuntu xenial InRelease Err:3 http://br.archive.ubuntu.com/ubuntu xenial InRelease Cannot initiate the connection to br.archive.ubuntu.com:80 (2801:82:80ff:8000::5). - connect (101: Network is unreachable) [IP: 2801:82:80ff:8000::5 80] Err:4 http://br.archive.ubuntu.com/ubuntu xenial-updates InRelease Cannot initiate the connection to br.archive.ubuntu.com:80 (2801:82:80ff:8000::5). - connect (101: Network is unreachable) [IP: 2801:82:80ff:8000::5 80] Err:5 http://br.archive.ubuntu.com/ubuntu xenial-backports InRelease Cannot initiate the connection to br.archive.ubuntu.com:80 (2801:82:80ff:8000::5). - connect (101: Network is unreachable) [IP: 2801:82:80ff:8000::5 80] Downloading 94,5 kB in 2min 0s (786 B/s) Reading package lists . Done W: Failed to fetch http://br.archive.ubuntu.com/ubuntu/dists/xenial/InRelease Cannot initiate the connection to br.archive.ubuntu.com:80 (2801:82:80ff:8000::5). - connect (101: Network is unreachable) [IP: 2801:82:80ff:8000::5 80] W: Failed to fetch http://br.archive.ubuntu.com/ubuntu/dists/xenial-updates/InRelease Cannot initiate the connection to br.archive.ubuntu.com:80 (2801:82:80ff:8000::5). - connect (101: Network is unreachable) [IP: 2801:82:80ff:8000::5 80] W: Failed to fetch http://br.archive.ubuntu.com/ubuntu/dists/xenial-backports/InRelease Cannot initiate the connection to br.archive.ubuntu.com:80 (2801:82:80ff:8000::5). - connect (101: Network is unreachable) [IP: 2801:82:80ff:8000::5 80] W: Some index files failed to download. They have been ignored, or old ones used instead. DISTRIB_ID=Ubuntu DISTRIB_RELEASE=16.04 DISTRIB_CODENAME=xenial DISTRIB_DESCRIPTION="Ubuntu 16.04.1 LTS"