RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 1758317 - nslookup / host do not honor the new search domain limits of glibc
Summary: nslookup / host do not honor the new search domain limits of glibc
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: bind
Version: 7.8
Hardware: Unspecified
OS: Unspecified
medium
medium
Target Milestone: rc
: ---
Assignee: Petr Menšík
QA Contact: qe-baseos-daemons
Mariya Pershina
URL:
Whiteboard:
Depends On:
Blocks: 1821287 1780577 1780662 1816141
TreeView+ depends on / blocked
 
Reported: 2019-10-03 20:25 UTC by Juan Manuel Santos
Modified: 2023-12-15 16:49 UTC (History)
8 users (show)

Fixed In Version:
Doc Type: Known Issue
Doc Text:
.`bind-utils` DNS lookup utilities support fewer search domains than `glibc` The `dig`, `host`, and `nslookup` DNS lookup utilities from the `bind-utils` package support only up to 8 search domains, while the `glibc` resolver in the system supports any number of search domains. As a consequence, the DNS lookup utilities may get different results than applications when a search in the `/etc/resolv.conf` file contains more than 8 domains. To work around this problem, use one of the following: * Full names ending with a dot, or * Fewer than nine domains in the `resolv.conf` search clause. Note that it is not recommended to use more than three domains.
Clone Of:
: 1816141 (view as bug list)
Environment:
Last Closed: 2020-03-30 08:48:38 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)

Comment 2 Petr Menšík 2019-10-04 08:47:32 UTC 
Public notes.

Search in nslookup is limited to 8 domains. 
When search in /etc/resolv.conf includes more than 8 domains, only first 8 are tried.

Limit was increased in glibc by bug #677316.
Comment 3 Petr Menšík 2019-10-04 08:55:04 UTC 
This number of searches is defined in lib/lwres/include/lwres/lwres.h

#define LWRES_CONFMAXSEARCH 8		/*%< max 8 domains in "search" entry */

No support for dynamic unlimited list is present.
Comment 4 Petr Menšík 2019-10-04 12:18:51 UTC 
Steps to Reproduce:
1. sed -i 's/^search .*/search non-existent1.very-long-domain.fedoraproject.org non-existent2.very-long-domain.fedoraproject.org non-existent3.very-long-domain.fedoraproject.org non-existent4.very-long-domain.fedoraproject.org non-existent5.very-long-domain.fedoraproject.org non-existent6.very-long-domain.fedoraproject.org openstacklocal redhat.com/' /etc/resolv.conf
2. [ "$(host access)" == "$(getent host access.redhat.com.)" ] && echo matches
3. sed -i 's/^search .*/search non-existent1.very-long-domain.fedoraproject.org non-existent2.very-long-domain.fedoraproject.org non-existent3.very-long-domain.fedoraproject.org non-existent4.very-long-domain.fedoraproject.org non-existent5.very-long-domain.fedoraproject.org non-existent6.very-long-domain.fedoraproject.org non-existent7.very-long-domain.fedoraproject.org non-existent8.very-long-domain.fedoraproject.org openstacklocal redhat.com/' /etc/resolv.conf
4. [ "$(host access)" == "$(getent host access.redhat.com.)" ] && echo still matches
Comment 5 Petr Menšík 2019-10-04 13:09:55 UTC 
Not even the most recent development version handles this different way. Reported upstream [1].

1. https://gitlab.isc.org/isc-projects/bind9/issues/1259
Comment 6 Tomáš Hozza 2019-12-16 11:36:10 UTC 
Patch submitted to upstream in https://gitlab.isc.org/isc-projects/bind9/merge_requests/2446
Comment 11 RHEL Program Management 2020-03-30 08:48:38 UTC 
Development Management has reviewed and declined this request. You may appeal this decision by using your Red Hat support channels, who will make certain  the issue receives the proper prioritization with product and development management.

https://www.redhat.com/support/process/production/#howto
Note You need to log in before you can comment on or make changes to this bug.