falha de segmentação OpenVPN

Question

falha de segmentação OpenVPN

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Eu tenho um servidor rodando o CentOS 5.7 e estou tentando fazer com que o OpenVPN 2.2.0 funcione. Para começar, eu já tinha trabalhado por um bom tempo agora, mas decidi tentar torná-lo altamente disponível usando heartbeat para failover em outro servidor. Agora eu não posso nem conseguir que funcione por algum motivo.

Sempre que eu tento iniciar o openvpn executando /etc/init.d/openvpn start , ele continua me dando o erro

/etc/init.d/openvpn: line 148: 5820 Segmentation fault $openvpn --daemon --writepid $piddir/$bn.pid --config $c --cd $work

Essa seção do script é:

 ...

 # Start every .conf in $work and run .sh if exists
        errors=0
        successes=0
        for c in '/bin/ls *.conf 2>/dev/null'; do
            bn=${c%%.conf}
            if [ -f "$bn.sh" ]; then
                . $bn.sh
            fi
            rm -f $piddir/$bn.pid
            $openvpn --daemon --writepid $piddir/$bn.pid --config $c --cd $work
            if [ $? = 0 ]; then
                successes=1
            else
                errors=1
            fi
        done
...

Aqui estão meus scripts de inicialização:

/ etc / openvpn / bridge-start

#!/bin/bash

. /etc/sysconfig/network-scripts/ifcfg-eth1

#################################
# Set up Ethernet bridge on Linux
# Requires: bridge-utils
#################################

# Define Bridge Interface
br="br0"

# Define list of TAP interfaces to be bridged,
# for example tap="tap0 tap1 tap2".
tap="tap0"

# Define physical ethernet interface to be bridged
# with TAP interface(s) above.
eth=$DEVICE
eth_ip=$IPADDR
eth_netmask=$NETMASK
eth_broadcast="10.224.45.159"

for t in $tap; do
    openvpn --mktun --dev $t
done

brctl addbr $br
brctl addif $br $eth

for t in $tap; do
    brctl addif $br $t
done

for t in $tap; do
    ifconfig $t 0.0.0.0 promisc up
done

ifconfig $eth 0.0.0.0 promisc up

ifconfig $br $eth_ip netmask $eth_netmask broadcast $eth_broadcast

/etc/openvpn/openvpn.conf

port        1194
proto       tcp

# Bridge
dev tap0
server-bridge   10.224.45.130 255.255.255.0 10.224.45.140 10.224.45.160

ca      /etc/openvpn/keys/ca.crt
cert        /etc/openvpn/keys/server.crt
key     /etc/openvpn/keys/server.key
dh      /etc/openvpn/keys/dh1024.pem
keepalive   10 120
status      /var/log/openvpn/status.log
log     /var/log/openvpn/openvpn.log
verb        0
client-to-client
comp-lzo
user nobody
group users
persist-key
persist-tun
client-cert-not-required
ifconfig-pool-persist ipp.txt
plugin /usr/lib64/openvpn/plugin/lib/openvpn-auth-ldap.so "/etc/openvpn/auth/ldap.conf"

/etc/openvpn/auth/ldap.conf

<LDAP>
        # LDAP server URL
        URL             ldap://ldap.****.com

        # Bind DN (If your LDAP server doesn't support anonymous binds)
        BindDN          uid=readonly,ou=Users,dc=****,dc=com

        # Bind Password
        Password        <hidden>

        # Network timeout (in seconds)
        Timeout         15

        # Follow LDAP Referrals (anonymously)
        FollowReferrals yes
</LDAP>

<Authorization>
        # Base DN
        BaseDN          "ou=Users,dc=****,dc=com"

        # User Search Filter
        SearchFilter    "(&(uid=%u))"

        # Require Group Membership
        RequireGroup    false
</Authorization>

Eu não tenho idéia de qual poderia ser a razão para o segfault. Eu pesquisei no Google por horas sem sorte em encontrar algo relacionado ao meu problema.

ATUALIZAÇÃO:

Saída de uname -a :

Linux master-srv1 2.6.18-274.7.1.el5xen #1 SMP Thu Oct 20 17:06:34 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux

Saída de yum info openvpn :

Installed Packages
Name       : openvpn
Arch       : x86_64
Version    : 2.2.0
Release    : 3.el5.rf
Size       : 1.0 M
Repo       : installed
Summary    : Robust and highly flexible VPN daemon
URL        : http://openvpn.net/
License    : GPL
Description: OpenVPN is a robust and highly flexible tunneling application.
           : 
           : OpenVPN supports SSL/TLS security, ethernet bridging, TCP or UDP tunnel
           : transport through proxies or NAT, support for dynamic IP addresses and
           : DHCP, scalability to hundreds or thousands of users, and portability to
           : most major OS platforms.

Saída de strace /etc/init.d/openvpn start : (Não foi possível ajustar toda a saída, então colei o final)

...

stat("/etc/sysconfig/network", {st_mode=S_IFREG|0644, st_size=79, ...}) = 0
access("/etc/sysconfig/network", X_OK)  = -1 EACCES (Permission denied)
access("/etc/sysconfig/network", R_OK)  = 0
open("/etc/sysconfig/network", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=79, ...}) = 0
read(3, "NETWORKING=yes\nNETWORKING_IPV6=y"..., 79) = 79
close(3)                                = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
stat("/usr/sbin/openvpn", {st_mode=S_IFREG|0755, st_size=614892, ...}) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 0), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x2b10685b9000
write(1, "Starting openvpn: ", 18Starting openvpn: )      = 18
rt_sigprocmask(SIG_BLOCK, [INT CHLD], [], 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [INT CHLD], 8) = 0
rt_sigprocmask(SIG_SETMASK, [INT CHLD], NULL, 8) = 0
lseek(255, -7, SEEK_CUR)                = 5545
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x2b1064fe4fe0) = 24440
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGINT, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 24440
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGCHLD (Child exited) @ 0 (0) ---
wait4(-1, 0x7fff46543fe4, WNOHANG, NULL) = -1 ECHILD (No child processes)
rt_sigreturn(0xffffffffffffffff)        = 0
rt_sigaction(SIGINT, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
stat("/etc/openvpn/openvpn-startup", {st_mode=S_IFREG|0740, st_size=143, ...}) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [INT CHLD], [], 8) = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x2b1064fe4fe0) = 24441
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGINT, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
wait4(-1, 
Running bridge-start...Done
[{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 24441
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGCHLD (Child exited) @ 0 (0) ---
wait4(-1, 0x7fff46544144, WNOHANG, NULL) = -1 ECHILD (No child processes)
rt_sigreturn(0xffffffffffffffff)        = 0
rt_sigaction(SIGINT, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
stat("/var/run/openvpn", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
stat("/var/lock/subsys/openvpn", 0x7fff46544910) = -1 ENOENT (No such file or directory)
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
open("/var/run/openvpn/", O_RDONLY|O_NONBLOCK|O_DIRECTORY) = 3
fcntl(3, F_SETFD, FD_CLOEXEC)           = 0
brk(0x1170c000)                         = 0x1170c000
getdents(3, /* 2 entries */, 32768)     = 48
getdents(3, /* 0 entries */, 32768)     = 0
brk(0x11704000)                         = 0x11704000
close(3)                                = 0
stat(".", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
stat("/sbin/rm", 0x7fff46544b50)        = -1 ENOENT (No such file or directory)
stat("/usr/sbin/rm", 0x7fff46544b50)    = -1 ENOENT (No such file or directory)
stat("/bin/rm", {st_mode=S_IFREG|0755, st_size=47088, ...}) = 0
access("/bin/rm", X_OK)                 = 0
access("/bin/rm", R_OK)                 = 0
stat("/bin/rm", {st_mode=S_IFREG|0755, st_size=47088, ...}) = 0
access("/bin/rm", X_OK)                 = 0
access("/bin/rm", R_OK)                 = 0
rt_sigprocmask(SIG_BLOCK, [INT CHLD], [], 8) = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x2b1064fe4fe0) = 24460
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGINT, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 24460
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGCHLD (Child exited) @ 0 (0) ---
wait4(-1, 0x7fff46544824, WNOHANG, NULL) = -1 ECHILD (No child processes)
rt_sigreturn(0xffffffffffffffff)        = 0
rt_sigaction(SIGINT, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
stat("/etc", {st_mode=S_IFDIR|0755, st_size=12288, ...}) = 0
stat("/etc/openvpn", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
chdir("/etc/openvpn")                   = 0
pipe([3, 4])                            = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [INT CHLD], [], 8) = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x2b1064fe4fe0) = 24461
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigaction(SIGCHLD, {0x436360, [], SA_RESTORER, 0x34e10302d0}, {0x436360, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
close(4)                                = 0
read(3, "openvpn.conf\n", 128)          = 13
read(3, "", 128)                        = 0
--- SIGCHLD (Child exited) @ 0 (0) ---
wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], WNOHANG, NULL) = 24461
wait4(-1, 0x7fff46544e94, WNOHANG, NULL) = -1 ECHILD (No child processes)
rt_sigreturn(0)                         = 0
close(3)                                = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGINT, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigaction(SIGINT, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
stat("openvpn.sh", 0x7fff46544840)      = -1 ENOENT (No such file or directory)
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
stat("/bin/rm", {st_mode=S_IFREG|0755, st_size=47088, ...}) = 0
access("/bin/rm", X_OK)                 = 0
access("/bin/rm", R_OK)                 = 0
rt_sigprocmask(SIG_BLOCK, [INT CHLD], [], 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [INT CHLD], 8) = 0
rt_sigprocmask(SIG_SETMASK, [INT CHLD], NULL, 8) = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x2b1064fe4fe0) = 24463
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGCHLD (Child exited) @ 0 (0) ---
wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], WNOHANG, NULL) = 24463
wait4(-1, 0x7fff46544684, WNOHANG, NULL) = -1 ECHILD (No child processes)
rt_sigreturn(0)                         = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGINT, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigaction(SIGINT, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
write(1, "/usr/sbin/openvpn --daemon --wri"..., 107/usr/sbin/openvpn --daemon --writepid /var/run/openvpn/openvpn.pid --config openvpn.conf --cd /etc/openvpn
) = 107
rt_sigprocmask(SIG_BLOCK, [INT CHLD], [], 8) = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x2b1064fe4fe0) = 24464
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGINT, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
wait4(-1, [{WIFSIGNALED(s) && WTERMSIG(s) == SIGSEGV}], 0, NULL) = 24464
fstat(2, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 0), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x2b10685ba000
open("/usr/share/locale/en_US.UTF-8/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en_US.utf8/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en_US/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en.UTF-8/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en.utf8/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
write(2, "/etc/init.d/openvpn: line 148: 2"..., 129/etc/init.d/openvpn: line 148: 24464 Segmentation fault      $openvpn --daemon --writepid $piddir/$bn.pid --config $c --cd $work
) = 129
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGCHLD (Child exited) @ 0 (0) ---
wait4(-1, 0x7fff46544b74, WNOHANG, NULL) = -1 ECHILD (No child processes)
rt_sigreturn(0xffffffffffffffff)        = 0
rt_sigaction(SIGINT, {SIG_DFL, [], SA_RESTORER, 0x34e10302d0}, {0x436f40, [], SA_RESTORER, 0x34e10302d0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
write(1, "[60G", 5                                      )                  = 5
write(1, "[", 1[)                        = 1
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
write(1, "[0;31m", 7)                = 7
write(1, "FAILED", 6FAILED)                   = 6
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
write(1, "[0;39m", 7)                = 7
write(1, "]", 1])                        = 1
)                       = 1
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
stat("/usr/bin/rhgb-client", 0x7fff465449a0) = -1 ENOENT (No such file or directory)
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
write(1, "\n", 1
)                       = 1
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
read(255, "exit 0\n", 5552)             = 7
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
exit_group(0)                           = ?

openvpn segmentation-fault centos

por Sarah Ryan 03.11.2011 / 06:46

2 respostas

0

Eu desinstala o heartbeat, ou pelo menos analiso os pacotes associados ao heartbeat. Eles fazem algo com interfaces de rede, se bem me lembro, e podem estar interferindo no tun0.

Não tenho certeza se essa é a melhor maneira de implementar o HA no OpenVPN. Minha impressão é que a maneira recomendada é usar várias linhas de "servidor" na configuração do cliente. Isso não será fácil, mas o OpenVPN não vai falhar de qualquer maneira, mesmo com o Heartbeat, porque a sessão precisará ser reinicializada.

por 03.11.2011 / 12:38

Tags openvpn segmentation-fault centos

Por que uma regra de roteamento específica é adicionada depois que a conexão VPN é configurada no Linux? Desistências intermitentes e resposta lenta em subdomínios - Route 53

score 1 · Accepted Answer

Boban P. estava absolutamente correto em seu comentário sobre o plugin openvpn-auth-ldap sendo a causa do segfault. Eu descartei isso inicialmente, já que eu comentei a saída do plugin e tentei reiniciar o openvpn e ele deu o mesmo erro. No entanto, o openvpn aparentemente ainda estava tentando usar o plugin, então ele ainda estava jogando o segfault. Eu não sei exatamente qual foi o problema com o plugin, mas meu melhor palpite é que instalei a versão incorreta para o meu sistema. Certifiquei-me de instalar o do CentOS a partir de link e funciona perfeitamente de novo.

O crédito deve ser dado a Boban P. por sua sugestão de que o openvpn-auth-ldap seja o assunto.