[root at localhost ~]# lsb_release -d Description: CentOS Linux release 8.2.2004 (Core) [root at localhost ~]# cat /etc/resolv.conf # Generated by NetworkManager search subdomain.company.com company.com nameserver 1.2.3.4 nameserver 5.6.7.8 [root at localhost ~]# host foo foo.subdomain.company.com has address 1.2.3.4 [root at localhost ~]# host foo.subdomain Host foo.subdomain not found: 3(NXDOMAIN) [root at localhost ~]# host foo.subdomain.company.com foo.subdomain.company.com has address 1.2.3.4 [root at localhost ~]# The expected result is that the lookup for foo.subdomain works, like it does under CentOS < 8. I tested this also on a RHEL8 machine and followed https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/configuring_and_managing_networking/manually-configuring-the-etc-resolv-conf-file_configuring-and-managing-networking to disable DNS processing by NM, but this did not change the outcome. How can the pre-CentOS 8 behaviour be restored?
On Thu, 2020-08-06 at 10:26 +0100, isdtor wrote:> [root at localhost ~]# lsb_release -d > Description: CentOS Linux release 8.2.2004 (Core) > [root at localhost ~]# cat /etc/resolv.conf > # Generated by NetworkManager > search subdomain.company.com company.com > nameserver 1.2.3.4 > nameserver 5.6.7.8 > > [root at localhost ~]# host foo > foo.subdomain.company.com has address 1.2.3.4 > > [root at localhost ~]# host foo.subdomain > Host foo.subdomain not found: 3(NXDOMAIN) > > [root at localhost ~]# host foo.subdomain.company.com > foo.subdomain.company.com has address 1.2.3.4 > [root at localhost ~]# > > The expected result is that the lookup for foo.subdomain works, like it does under CentOS < 8.man host -N ndots The number of dots that have to be in name for it to be considered absolute. The default value is that defined using the ndots statement in /etc/resolv.conf, or 1 if no ndots statement is present. Names with fewer dots are interpreted as relative names and will be searched for in the domains listed in the search or domain directive in /etc/resolv.conf. P.
Pete Biggs writes:> On Thu, 2020-08-06 at 10:26 +0100, isdtor wrote: > > [root at localhost ~]# lsb_release -d > > Description: CentOS Linux release 8.2.2004 (Core) > > [root at localhost ~]# cat /etc/resolv.conf > > # Generated by NetworkManager > > search subdomain.company.com company.com > > nameserver 1.2.3.4 > > nameserver 5.6.7.8 > > > > [root at localhost ~]# host foo > > foo.subdomain.company.com has address 1.2.3.4 > > > > [root at localhost ~]# host foo.subdomain > > Host foo.subdomain not found: 3(NXDOMAIN) > > > > [root at localhost ~]# host foo.subdomain.company.com > > foo.subdomain.company.com has address 1.2.3.4 > > [root at localhost ~]# > > > > The expected result is that the lookup for foo.subdomain works, like it does under CentOS < 8. > > man host > > -N ndots > The number of dots that have to be in name for it to be considered absolute. The default value is that defined using > the ndots statement in /etc/resolv.conf, or 1 if no ndots statement is present. Names with fewer dots are interpreted > as relative names and will be searched for in the domains listed in the search or domain directive in > /etc/resolv.conf.As per man resolv.conf, the default setting hasn't changed. It is n=1 on all of CentOS 6/7/8.