<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hi,<div class="">thanks a lot Brian, </div><div class="">and thanks to Sahid (for his help today, in french :) )</div><div class="">Problem is very small MTU.</div><div class=""><div class="">a user (student) created a network with a small mtu (on the day of the final exam) and for the rest of the day, no more dhcp....</div><div class="">The problem is addressed here: <a href="https://bugs.launchpad.net/neutron/+bug/1988069" class="">https://bugs.launchpad.net/neutron/+bug/1988069</a></div><div class=""><br class=""></div><div class="">Before I have time to update, if it happens again, I will know what to do…</div></div><div class=""><br class=""></div><div class=""><div class="">Thanks a lot</div><div class=""><br class=""></div><div class=""><br class=""><div class="">
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<div><br class=""><blockquote type="cite" class=""><div class="">Le 5 avr. 2023 à 15:37, Brian Haley <<a href="mailto:haleyb.dev@gmail.com" class="">haleyb.dev@gmail.com</a>> a écrit :</div><br class="Apple-interchange-newline"><div class=""><meta charset="UTF-8" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Hi,</span><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">On 4/5/23 2:57 AM, Franck VEDEL wrote:</span><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><blockquote type="cite" style="font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">Hi , and thanks a lot for your help.<br class="">so<br class="">$ sudo ip netns exec qdhcp-8db375e0-28d2-4379-9330-397dc9b4f2b1 ip a<br class="">3401: tap1c220d25-b9: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 68qdisc noqueue state UNKNOWN group default qlen 1000<br class=""> <span class="Apple-converted-space"> </span>link/ether fa:16:3e:20:ef:bc brd ff:ff:ff:ff:ff:ff<br class=""> <span class="Apple-converted-space"> </span>inet 169.254.169.254/32 brd 169.254.169.254 scope global tap1c220d25-b9<br class=""> valid_lft forever preferred_lft forever<br class=""> <span class="Apple-converted-space"> </span>inet 10.1.42.1/24 brd 10.1.42.255 scope global tap1c220d25-b9<br class=""> valid_lft forever preferred_lft forever<br class=""></blockquote><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Ok, so it is as I thought, someone has set a very small mtu on a network.</span><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><blockquote type="cite" style="font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">$tail -f /var/log/kolla/neutron/neutron-dhcp-agent.log |grep 8db375e0-28d2-4379-9330-397dc9b4f2b1<br class="">2023-04-05 08:36:11.558 7 INFO neutron.agent.dhcp.agent [-] Starting network 8db375e0-28d2-4379-9330-397dc9b4f2b1 dhcp configuration<br class="">2023-04-05 08:36:12.532 7 ERROR neutron.agent.dhcp.agent [-] Unable to enable dhcp for 8db375e0-28d2-4379-9330-397dc9b4f2b1.: neutron.privileged.agent.linux.ip_lib.InvalidArgument: Invalid parameter/value used on interface tap1c220d25-b9, namespace qdhcp-8db375e0-28d2-4379-9330-397dc9b4f2b1.<br class="">2023-04-05 08:36:12.532 7 ERROR neutron.agent.dhcp.agent neutron.privileged.agent.linux.ip_lib.InvalidArgument: Invalid parameter/value used on interface tap1c220d25-b9, namespace qdhcp-8db375e0-28d2-4379-9330-397dc9b4f2b1.<br class="">2023-04-05 08:36:12.534 7 INFO neutron.agent.dhcp.agent [-] Finished network 8db375e0-28d2-4379-9330-397dc9b4f2b1 dhcp configuration<br class="">openstack network show 8db375e0-28d2-4379-9330-397dc9b4f2b1<br class="">+---------------------------+--------------------------------------+<br class="">| Field | Value |<br class="">+---------------------------+--------------------------------------+<br class="">| admin_state_up | UP |<br class="">| availability_zone_hints | |<br class="">| availability_zones | nova |<br class="">| created_at | 2023-04-04T11:49:47Z |<br class="">| description | |<br class="">| dns_domain | None |<br class="">| id | 8db375e0-28d2-4379-9330-397dc9b4f2b1 |<br class="">| ipv4_address_scope | None |<br class="">| ipv6_address_scope | None |<br class="">| is_default | None |<br class="">| is_vlan_transparent | None |<br class="">| mtu |68 |<br class="">| name | NET1 |<br class="">| port_security_enabled | True |<br class="">| project_id | 6d6cbcbb6e8d4264bcd13dd8b3d79466 |<br class="">| provider:network_type | vxlan |<br class="">| provider:physical_network | None |<br class="">| provider:segmentation_id | 456 |<br class="">| qos_policy_id | None |<br class="">| revision_number | 2 |<br class="">| router:external | Internal |<br class="">| segments | None |<br class="">| shared | False |<br class="">| status | ACTIVE |<br class="">| subnets |b72cf65c-1a22-4165-a55b-884bcc9c636a|<br class="">| tags | |<br class="">| updated_at | 2023-04-04T11:49:47Z |<br class="">+---------------------------+———————————————————+<br class=""></blockquote><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Increasing the mtu on this network to at least 1280 should fix the issue with DHCP, that is the IPv6 minimum mtu and most likely causing the issue. You should check other networks and use the same value, but it is probably 1450 given the overlay is vxlan.</span><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Since this is a known issue, there is no need for a new bug, but for your reference you can go to<span class="Apple-converted-space"> </span></span><a href="https://bugs.launchpad.net/neutron" style="font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">https://bugs.launchpad.net/neutron</a><span style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class=""><span class="Apple-converted-space"> </span>to search and file a new one.</span><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Thanks,</span><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">-Brian</span><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><blockquote type="cite" style="font-family: Verdana; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">$openstack subnet showb72cf65c-1a22-4165-a55b-884bcc9c636a<br class="">+----------------------+--------------------------------------+<br class="">| Field | Value |<br class="">+----------------------+--------------------------------------+<br class="">| allocation_pools | 10.1.42.1-10.1.42.253 |<br class="">| cidr | 10.1.42.0/24 |<br class="">| created_at | 2023-04-04T11:49:47Z |<br class="">| description | |<br class="">| dns_nameservers | |<br class="">| dns_publish_fixed_ip | None |<br class="">| enable_dhcp | True |<br class="">| gateway_ip | 10.1.42.254 |<br class="">| host_routes | |<br class="">| id | b72cf65c-1a22-4165-a55b-884bcc9c636a |<br class="">| ip_version | 4 |<br class="">| ipv6_address_mode | None |<br class="">| ipv6_ra_mode | None |<br class="">| name | |<br class="">| network_id | 8db375e0-28d2-4379-9330-397dc9b4f2b1 |<br class="">| project_id | 6d6cbcbb6e8d4264bcd13dd8b3d79466 |<br class="">| revision_number | 0 |<br class="">| segment_id | None |<br class="">| service_types | |<br class="">| subnetpool_id | None |<br class="">| tags | |<br class="">| updated_at | 2023-04-04T11:49:47Z |<br class="">+----------------------+--------------------------------------+<br class="">Since yesterday, we have a lot of network (2 per students , 100 students) , so a lot of errors:<br class="">In the log of dnsmask we can see this:<br class="">Apr 5 08:55:02 dnsmasq-dhcp[2466928]: read /var/lib/neutron/dhcp/7d33855e-03a8-431b-9cf8-64f8e95b8f93/host<br class="">Apr 5 08:55:02 dnsmasq-dhcp[2466928]: read /var/lib/neutron/dhcp/7d33855e-03a8-431b-9cf8-64f8e95b8f93/opts<br class="">Apr 5 08:55:05 dnsmasq-dhcp[609053]: DHCPDISCOVER(tap5af0e639-f3) fa:16:3e:8d:86:b9 no address available<br class="">Apr 5 08:55:05 dnsmasq-dhcp[4572]: DHCPDISCOVER(tap6fe70972-c9) fa:16:3e:6d:dc:c8 no address available<br class="">You say: If that's not it please file a new bug with all the above info provided.<br class="">How can I do that ?<br class="">Thanks a lot<br class="">Franck<br class=""><blockquote type="cite" class="">Le 5 avr. 2023 à 00:00, Brian Haley <<a href="mailto:haleyb.dev@gmail.com" class="">haleyb.dev@gmail.com</a><span class="Apple-converted-space"> </span><<a href="mailto:haleyb.dev@gmail.com" class="">mailto:haleyb.dev@gmail.com</a>>> a écrit :<br class=""><br class="">8db375e0-28d2-4379-9330-397dc9b4f2b1</blockquote></blockquote></div></blockquote></div><br class=""></div></div></body></html>