[squid-users] squid stops replying

[Vieri]

Hi,

After a long time working correctly, Squid stops working all of a sudden.

No new requests/replies show up in the logs. Complete silence.

If I issue "squid -k reconfigure" I get this message in cache.log:
Set Current Directory to /var/cache/squid

If I set "debug_options rotate=1 ALL,9" and run "squid -k reconfigure" twice then I get this in cache.log:

2017/08/23 07:54:32.676| 21,3| tools.cc(610) enter_suid: enter_suid: PID 17797 taking root privileges
2017/08/23 07:54:32.676| 13,3| mem.cc(473) Report: Memory pools are 'on'; limit: 5.000 MB
2017/08/23 07:54:32.676| Set Current Directory to /var/cache/squid
2017/08/23 07:54:32.676| 21,3| tools.cc(543) leave_suid: leave_suid: PID 17797 called
2017/08/23 07:54:32.676| 21,3| tools.cc(565) leave_suid: leave_suid: PID 17797 giving up root, becoming 'squid'
2017/08/23 07:55:01.605| 21,3| tools.cc(610) enter_suid: enter_suid: PID 17927 taking root privileges
2017/08/23 07:55:01.605| 13,3| mem.cc(473) Report: Memory pools are 'on'; limit: 5.000 MB
2017/08/23 07:55:01.605| Set Current Directory to /var/cache/squid
2017/08/23 07:55:01.605| 21,3| tools.cc(543) leave_suid: leave_suid: PID 17927 called
2017/08/23 07:55:01.605| 21,3| tools.cc(565) leave_suid: leave_suid: PID 17927 giving up root, becoming 'squid'

However, any attempt to browse the web leads to nothing new in the logs.

Finally, stopping the squid service fails. I can list the squid processes: 

# ps -ae | grep squid
4439 ?        05:29:57 squid
9059 ?        00:00:00 squid
9160 ?        00:00:00 squid
9162 ?        00:11:42 squid
9206 ?        00:00:00 squid
9208 ?        00:02:04 squid
9254 ?        00:00:00 squid
9257 ?        00:00:28 squid
9313 ?        00:00:00 squid
9315 ?        00:00:55 squid

I have to kill these processes in order to start squid again.

# squid -version
Squid Cache: Version 3.5.26
Service Name: squid

This binary uses OpenSSL 1.0.2k  26 Jan 2017. For legal restrictions on distribution see https://www.openssl.org/source/license.html

configure options:  '--prefix=/usr' '--build=x86_64-pc-linux-gnu' '--host=x86_64-pc-linux-gnu' '--mandir=/usr/share/man' '--infodir=/usr/share/info' '--datadir=/usr/share' '--sysconfdir=/etc' '--localstatedir=/var/lib' '--disable-dependency-tracking' '--disable-silent-rules' '--docdir=/usr/share/doc/squid-3.5.26' '--htmldir=/usr/share/doc/squid-3.5.26/html' '--libdir=/usr/lib64' '--sysconfdir=/etc/squid' '--libexecdir=/usr/libexec/squid' '--localstatedir=/var' '--with-pidfile=/run/squid.pid' '--datadir=/usr/share/squid' '--with-logdir=/var/log/squid' '--with-default-user=squid' '--enable-removal-policies=lru,heap' '--enable-storeio=aufs,diskd,rock,ufs' '--enable-disk-io' '--enable-auth-basic=MSNT-multi-domain,NCSA,POP3,getpwnam,SMB,LDAP,PAM,RADIUS' '--enable-auth-digest=file,LDAP,eDirectory' '--enable-auth-ntlm=smb_lm' '--enable-auth-negotiate=kerberos,wrapper' '--enable-external-acl-helpers=file_userip,session,unix_group,wbinfo_group,LDAP_group,eDirectory_userip,kerberos_ldap_group' '--enable-log-daemon-helpers' '--enable-url-rewrite-helpers' '--enable-cache-digests' '--enable-delay-pools' '--enable-eui' '--enable-icmp' '--enable-follow-x-forwarded-for' '--with-large-files' '--disable-strict-error-checking' '--disable-arch-native' '--with-ltdl-includedir=/usr/include' '--with-ltdl-libdir=/usr/lib64' '--with-libcap' '--enable-ipv6' '--disable-snmp' '--with-openssl' '--with-nettle' '--with-gnutls' '--enable-ssl-crtd' '--disable-ecap' '--disable-esi' '--enable-htcp' '--enable-wccp' '--enable-wccpv2' '--enable-linux-netfilter' '--with-mit-krb5' '--without-heimdal-krb5' 'build_alias=x86_64-pc-linux-gnu' 'host_alias=x86_64-pc-linux-gnu' 'CC=x86_64-pc-linux-gnu-gcc' 'CFLAGS=-O2 -pipe' 'LDFLAGS=-Wl,-O1 -Wl,--as-needed' 'CXXFLAGS=-O2 -pipe' 'PKG_CONFIG_PATH=/usr/lib64/pkgconfig'

What can I try if this happens again?

Thanks,

Vieri