ECS: Falha no bloqueio de nó devido ao limitador de taxa SSH no nó
Summary: Após o upgrade para o ECS 4.0, as tentativas de bloquear um nó poderão falhar se um limitador de taxa de SSH estiver ativo no nó. Isso faz com que o status do nó apareça como "desconhecido" ou "bloqueado" na IU da Web do ECS, enquanto o acesso SSH permanece disponível. Uma regra STIG que aplica um limitador de taxa SSH, que não é compatível com SLES15, causa esse problema. ...
Symptoms
Problema observado após o upgrade para o ECS 4.0.
O status do nó é exibido como "desconhecido" ou "bloqueado" na IU da Web do ECS.
Falha na execução do comando de bloqueio da CLI.
O acesso SSH ao nó permanece disponível, apesar da tentativa de bloqueio.
Cause
A presença de um limitador de taxa SSH aplicado usando uma regra STIG (SLES-12-030040) causa esse problema. Essa regra não é compatível com o SLES15 e, uma vez aplicada, não pode ser revertida usando a estrutura SLES12 STIG.
O comando abaixo exibe informações sobre o sistema operacional:
admin@node1:~> cat /etc/os-release
NAME="SLES"
VERSION="15-SP4"
VERSION_ID="15.4"
PRETTY_NAME="SUSE Linux Enterprise Server 15 SP4"
ID="sles"
ID_LIKE="suse"
ANSI_COLOR="0;32"
CPE_NAME="cpe:/o:suse:sles:15:sp4"
DOCUMENTATION_URL="https://documentation.suse.com/"Resolution
Para resolver o problema, remova o limitador de taxa SSH do(s) nó(s) afetado(s):
- Verifique o limitador de taxa SSH:
admin@node1:~> sudo iptables -L | grep limit | grep ssh LOG tcp -- anywhere anywhere limit: avg 3/min burst 5 tcp dpt:ssh ctstate NEW recent: CHECK seconds: 60 hit_count: 3 name: ssh side: source mask: 255.255.255.255 LOG level warning tcp-options ip-options prefix "SFW2-INext-DROPr "
- Reverta a regra STIG:
admin@node1:~> cd /opt/emc/security/hardening/root/sbin; sudo ./revert-harden -i SLES-12-030040 Changes reverted: FW_SERVICES_ACCEPT_EXT="0/0,tcp,22,,hitcount=3,blockseconds=60,recentname=ssh" FW_SERVICES_ACCEPT_EXT="0/0,tcp,22,,hitcount=3,blockseconds=60,recentname=ssh" Changes reverted: TCP="ssh" Restarting SuSEfirewall2.service ... SuSEfirewall2.service restarted successfully. Reverted STIG ID: SLES-12-030040 on /etc/sysconfig/SuSEfirewall2.d/services/sshd successfully
- Verifique as alterações:
admin@node1:/opt/emc/security/hardening/root/sbin> sudo iptables -L | grep limit | grep ssh
- Bloqueie o nó usando a interface do usuário da Web ou a CLI:
admin@node1:~> sudo -i lockdown set lock [lockdown] :Info: Suspend fabric agent firewall check INFO: Parsing /opt/emc/nile/etc/conf/nan/emc-firewall-cfg dev_ext: public - dev_int: private private.4 pslave-0 pslave-1 INFO: Updating /etc/sysconfig/SuSEfirewall2.d/services/emc-ecs-custom INFO: Updating /etc/sysconfig/SuSEfirewall2 <38>Jun 25 10:34:47 SuSEfirewall2[32514]: Firewall rules unloaded. <38>Jun 25 10:34:47 SuSEfirewall2[32594]: Setting up rules from /etc/sysconfig/SuSEfirewall2 ... <38>Jun 25 10:34:47 SuSEfirewall2[32594]: using default zone 'ext' for interface docker0 <38>Jun 25 10:34:47 SuSEfirewall2[32594]: using default zone 'ext' for interface public_mgmt <38>Jun 25 10:34:47 SuSEfirewall2[32594]: using default zone 'ext' for interface slave_0 <38>Jun 25 10:34:47 SuSEfirewall2[32594]: using default zone 'ext' for interface slave_1 <38>Jun 25 10:34:47 SuSEfirewall2[32594]: Firewall custom rules loaded from /opt/emc/nile/etc/conf/nan/nan_pbr_rules <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/all/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/default/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/docker0/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/lo/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/private/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/pslave-0/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/pslave-1/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/public/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:48 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/slave-0/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:49 SuSEfirewall2[32594]: /proc/sys/net/ipv4/conf/slave-1/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:49 SuSEfirewall2[32594]: Firewall rules successfully set INFO: Updating /etc/sysconfig/SuSEfirewall2 <38>Jun 25 10:34:57 SuSEfirewall2[35003]: Firewall rules unloaded. <38>Jun 25 10:34:57 SuSEfirewall2[35084]: Setting up rules from /etc/sysconfig/SuSEfirewall2 ... <38>Jun 25 10:34:57 SuSEfirewall2[35084]: using default zone 'ext' for interface docker0 <38>Jun 25 10:34:57 SuSEfirewall2[35084]: using default zone 'ext' for interface public_mgmt <38>Jun 25 10:34:57 SuSEfirewall2[35084]: using default zone 'ext' for interface slave_0 <38>Jun 25 10:34:57 SuSEfirewall2[35084]: using default zone 'ext' for interface slave_1 <38>Jun 25 10:34:57 SuSEfirewall2[35084]: Firewall custom rules loaded from /opt/emc/nile/etc/conf/nan/nan_pbr_rules <38>Jun 25 10:34:57 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/all/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:57 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/default/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:57 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/docker0/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:57 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/lo/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:57 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/private/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:58 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/pslave-0/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:58 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/pslave-1/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:58 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/public/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:58 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/slave-0/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:58 SuSEfirewall2[35084]: /proc/sys/net/ipv4/conf/slave-1/rp_filter override in /etc/sysctl.d/70-nan-performance.conf, not setting it <38>Jun 25 10:34:59 SuSEfirewall2[35084]: Firewall rules successfully set locked [lockdown] :Info: Resume fabric agent firewall check
Additional Information
Essa solução temporária é aplicável somente aos nós que executam o SLES15 em que a estrutura SLES12 STIG foi aplicada anteriormente. Verifique a compatibilidade antes de aplicar ou reverter regras STIG.